Friday

July 3, 2015

July 3, 2015

Number of results: 41,141

**physics**

A rock is tossed straight up with a velocity of 34.0 m/s. When it returns, it falls into a hole 17.3 m deep. What is the rock's velocity as it hits the bottom of the hole? How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
*October 8, 2010 by Andres*

**physics**

A rock is tossed straight up with a velocity of 37.1 m/s. When it returns, it falls into a hole 18.8 m deep. What is the rock's velocity as it hits the bottom of the hole?
*October 6, 2008 by Vishnu*

**Physics**

A rock is tossed straight up with a velocity of 32.1 m/s. When it returns, it falls into a hole 20.1 m deep. What is the rock's velocity as it hits the bottom of the hole?
*October 4, 2010 by Bala*

**Physics**

A rock is tossed straight up with a velocity of 33.9 m/s. When it returns, it falls into a hole 11.9 m deep. What is the rock's velocity as it hits the bottom of the hole?
*October 4, 2010 by Em*

**Phyiscs**

A rock is tossed straight up with a velocity of 33.9 m/s. When it returns, it falls into a hole 11.9 m deep. What is the rock's velocity as it hits the bottom of the hole?
*October 4, 2010 by Em*

**Physics**

A rock is tossed straight up with a velocity of 33.9 m/s. When it returns, it falls into a hole 11.9 m deep. What is the rock's velocity as it hits the bottom of the hole?
*October 4, 2010 by Em*

**physics**

A rock is tossed straight up with a speed of 29m/s. When it returns, it falls into a hole 13m deep. Solve for rock's velocity as it hits the bottom of the hole. &How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
*June 12, 2012 by Amanda*

**physics**

A rock is tossed straight up with a velocity of 37.1 m/s. When it returns, it falls into a hole 18.8 m deep. How long is the rock in the air, from the instant it is released until it hits the bottom of the hole?
*October 7, 2008 by Deepa*

**physics**

A rock is tossed straight up with a velocity of 37.1 m/s. When it returns, it falls into a hole 18.8 m deep. What is the rock's velocity as it hits the bottom of the hole? Responses The gain in kinetic energy equals the loss of potential energy. (1/2) M (V2^ - V1^2) = M g *(18...
*October 8, 2008 by Vishnu*

**phisics**

a rock is tossed straight up with a speed of 30m/s. when it returns it falls into a hole 10m deep. what is the rocks velocity as it hits the bottom of the whole? how long would the rock in the air, form the instant it is released until it hits the bottom on the hole
*August 30, 2012 by nicolas*

**University Physics**

A rock is tossed straight up with an initial speed of 20 m/s. When it returns, it fall into a hole that is 8.0 m deep. What is the velocity of the rock (in m/s) when it hits the bottom of the hole? Use -9.80 m/s2 for the local acceleration due to gravity and assume no ...
*September 12, 2011 by Me*

**physics**

A rock is tossed straight up with a velocity of 37.1 m/s. When it returns, it falls into a hole 18.8 m deep. What is the rock's velocity as it hits the bottom of the hole? Responses The gain in kinetic energy equals the loss of potential energy. (1/2) M (V2^ - V1^2) = M g *(18...
*October 8, 2008 by Vishnu*

**Math**

For this problem, a person standing on the edge of a cliff throws a rock directly upward. it is observed that 2 secs later the rock is at its maximum height (in feet) and that 5 secs after that (meaning 7 seconds after being thrown) the rock hits the ground at the base of the ...
*October 7, 2014 by Leah*

**Calculus**

A blast blows a rock straight up at 150 ft/sec. The path of the rock is described by the s(t) = 150t-16t^2 where s is measured in feet and t in seconds. Find the velocity of the rock when it is 200 ft above the ground and when the rock hits the ground.
*February 18, 2012 by Desperate!!!!*

**physics**

a rock is dropped from a height of 15m above the ground. when it hits the ground, it leaves a hole 12cm deep. what is the speed of the rock when it hits the ground? what is the deceleration of the rock when it hits the ground?
*September 21, 2011 by Taylor*

**physics**

a rock is dropped from a height of 15m above the ground. when it hits the ground, it leaves a hole 12cm deep. what is the speed of the rock when it hits the ground? what is the deceleration of the rock when it hits the ground?
*September 21, 2011 by Taylor*

**Physics**

One can get a good idea of how deep a well is, for example, by dropping a rock and listening to how long it take to hear the rock as it hits the bottom. Suppose a rock was dropped into a well that was 410 meters deep and after the rock hits the bottom, a sound wave travels at ...
*September 16, 2011 by Jeff J.*

**Physics**

A hiker throws a rock with a mass of 1.4kg from a cliff that is 37 m above the ground . The hiker gives the rock an initial downward velocity of 8.5 m/s. a) What is the energy of the rock at the moment the hiker releases it? b) What is the velocity of the rock at the moment it...
*May 4, 2014 by cee*

**Alg 1**

Landon is standing in a hole that is 6.5 ft deep. He throws a rock and it goes up into the air, out of the hole, and then lands on the ground above. The path of the rock can be modeled by the equation y = -0.005x^2 + 0.45x - 6.5, where x is the horizontal distance of the rock...
*April 16, 2013 by Jane*

**Math-Help**

A rock is tossed straight up into the air. The height h (in feet) t seconds after it is tossed is given by the function: h(t)=-16t^2+100.4t+5.1 (a) Make a table of values for 0 to 10 seconds. (b) Graph the function. (c) What is the initial height of the rock? (d) When did the ...
*April 28, 2014 by Kevin*

**Math**

4. Landon is standing in a hole that is 6.5 ft deep. He throws a rock, and it goes up into the air, out of the hole, and then lands on the ground above. The path of the rock can be modeled by the equation y = 0.005x² + 0.45x – 6.5, where x is the horizontal distance of the ...
*March 11, 2013 by Jim*

**math**

Landon is standing in a hole that is 6.7 ft deep. He throws a rock and it goes up into the air, out of the hole, and then lands on the ground above. the path of the rock can be modeled by the equation y= -0.005x^2 + 0.48x - 6.7, where x is the horizontal distance of the rock, ...
*April 26, 2012 by Jane*

**physics**

a rock hits the ground at a speed of 10m/s and leaves a hole 25cm deep. what is the magnitude of the (assumed) uniform deceleration of the rock?
*September 17, 2011 by yazan*

**Physics**

A rock is thrown horizontally from a bridge with a velocity of 13.0 m/s. It takes the rock 3.5 s to strike the water below. What is the magnitude of the velocity of the rock just before it hits the water?
*February 2, 2015 by Vishal *

**pre-cal **

aj uses a lingshot to launch a rock straight up from the a point of 6 ft. above ground level with an initial velocity of 170 ft per second. A) find an equation that models the height of the rock t seconds after it is launched. b) what is the maximum height of the rock and when...
*October 24, 2012 by jhon avendano*

**physics**

A catapult gives a rock a vertical velocity of 122m/s. a. Determine the time the rock is in the air. b. Determine the maximum height the rock would reach. c. As the rock leaves the catapult the rock also has a horizontal velocity of 34m/s. solve for the rocks range. d. Solve ...
*November 19, 2012 by Sadie*

**Physics**

A dynamite blast sends a piece of rock (shatter) straight upwards. After 2.31x10^0 s the piece of rock has a velocity of 1.56x10^1 m/s. Assuming there is no air resistance, what is the initial velocity of the rock, to two significant figures?
*October 14, 2010 by peter*

**Calc**

If a rock is thrown upward on the planet Mars with a velocity of 17 m/s, its height (in meters) after t seconds is given by H = 17t − 1.86t^2. (a) Find the velocity of the rock after one second. (b) Find the velocity of the rock when t = a. (c) When will the rock hit the...
*October 17, 2011 by Katrina*

**physical science**

A rock thrown straight up climbs for 4.24 s, then falls to the ground. Neglecting air resistance, with what velocity did the rock strike the ground?
*January 30, 2014 by Coya*

**Physical Science**

A rock thrown straight up climbs for 2.50 s,the falls to the ground. Neglecting the air resistance, with wat velocity did the rock strike the ground?
*March 6, 2010 by Julie*

**Physics**

A rock is dropped of the side of a bridge and hits the water below 4s later. a. What was the rock’s velocity when it hit the water? b. What was the rock’s average velocity as it fell? c. What is the height of the bridge above the water?
*April 6, 2010 by Jackie*

**ALGEBRA**

The velocity v (in feet per second) of a rock dropped into a well is related to time (in seconds) by the formula v = 32t. What is the velocity of the rock at the indicated instant? Write your answer in the form (t, v). (a) when the rock is released ( , ) (b) after 9 seconds
*April 25, 2012 by Randy*

**Calculus**

well i have this homework question that says: A rock is dropped from the top of a 300-ft cliff. It's velocity at time t seconds is v(t0= -32 t feet per second. a.) Find the height of the rock above the ground at time t. b.) How long will the rock take to reach the ground? c.) ...
*May 11, 2009 by Caitlin*

**physics**

A rock is dropped from a treetop 19.6 m high, and then, 1.00 s later, a second rock is thrown down. With what initial velocity must the second rock be thrown if it is to reach the ground at the same time as the first? I'm not sure how to find the initial velocity of the thrown...
*February 10, 2013 by Wes*

**Physics**

Two rocks are thrown off the edge of a cliff that is 15.0 m above the ground. The first rock is thrown upward, at a velocity of +12.0 m/s. The second is thrown downward, at a velocity of −12.0 m/s. Ignore air resistance. Determine (a) how long it takes the first rock to ...
*September 12, 2010 by Sandy*

**Physics **

A rock is thrown into a railroad car standing on a level frictionless track. If the rock has a mass of ms = 1.100 kg and is tossed with a velocity v = 6.3 m/s, how far up will the car go (mc = 5.400 kg) before stopping? Please explain
*January 4, 2014 by Harriet*

**physics**

A balloon carrying a basket is descending at a constant velocity of 20.0 m/s. A person in the basket throws a stone with an initial velocity of 15.0 m/s horizontally perpendicular to the path of the descending balloon, and 4.00s later this person sees the rock strike the ...
*February 9, 2008 by Erin*

**Earth Science**

1. In the classroom during a visual inspection of a rock, a student recorded four statements about the rock. Which statement about the rock is an observation? (1)The rock formed deep in Earthâ€™s interior. (2)The rock cooled very rapidly. (3)The rock dates from the Cambrian ...
*June 18, 2008 by Anonymous*

**Physics**

. A rock is thrown up into the air with an initial velocity of 15m/s up. What is the rock's velocity after 0.40 seconds?
*June 8, 2014 by Bob*

**11th grade**

a rock is dropped from a 20.0m bridge falls into the river below. a.)at whqat velocity does it strike the water? b.)how much time did the rock take to reach the water?
*December 12, 2010 by marissa*

**physics**

The acceleration due to the moon's gravity at its surface is less than what it is here on the surface of the earth. The computed value of 1.6 m/s2 is consistent with what the Apollo Program astronauts observed during their explorations there. Imagine an astronaut holding a ...
*October 2, 2013 by becca*

**PHYSICS**

A ROCK IS THROWN OFF A CLIFF WITH AN HORIZONTAL VELOCITY OF 55.0 M/SEC. IT TAKES THE ROCK 7.0 SEC TO HIT THE GROUND A)WHAT IS THE HEIGHT OF THE CLIFF B) HOW FAR FROM THE FOOT OF THE CLIFF DOES THE ROCK HIT THE GROUND C)WHAT IS THE HORIZONTAL COMPONENT OF VELOCITY WITH WHICH ...
*October 16, 2011 by HELPPPPPPP*

**physics**

a rock is thrown of a cliff with an horizontal velocity of 55.0 m/sec. it takes the rock 7.0 sec to hit the ground a) what is the height of the cliff. b)how far from the foot of the cliff does the rock hit the ground. c) what is the vertical component of velocity with which ...
*October 15, 2011 by ru*

**Ýndustrial Engineering**

The figure shows the paths of a golf ball your friend drops from the window of her apartment and of the rock you throw from the ground at the same instant. The rock and the ball collide at x = 41.00 m, y = 17.02 m, and t = 2.94 s. If the ball was dropped from a height of h = ...
*March 18, 2013 by Ozgun*

**physics - density**

A person got a metal rock, he knows this rock density is ρm, but he is worried that there might be a hole within the rock, how he found there is a hole or not? And how he found the fraction of the hole size to total rock size? write your experimental steps.
*November 13, 2008 by Anonymous*

**Physics**

a rock is thrown straight up which of the following statemetns concerning the net force acting on the rock at teh top of the path is true? assume air resistance is negligible. a)it's equal to the weight of the rock b) it is instantanwously equal to zero c) it's direction ...
*November 14, 2007 by Andrea*

**physics**

Frank stands at the base of a building. He throws a 0.12kg rock straight up at a speed of 28m/s so that it rises to a maximum height of 12m above the top of the building and then falls straight down on the roof of the building. a) What is the height of the building? b) What is...
*April 18, 2010 by bob*

**Physics Gr.11**

Frank stands at the base of a building. He throws a 0.12kg rock straight up at a speed of 28m/s so that it rises to a maximum height of 12m above the top of the building and then falls straight down on the roof of the building. a) What is the height of the building? b) What is...
*April 18, 2010 by NINI*

**physics**

a rock weighing 20.0N falls from a height of 16.0m and sinks 0.600 m into the ground. from energy considerations, find the average force between the rock and the ground as the rock sinks. (avg. force) x (distance sunk) is the3 work done by the soil in decelerating the rock ...
*September 13, 2006 by Maggie*

**PHYSÝCS**

The figure shows the paths of a golf ball your friend drops from the window of her apartment and of the rock you throw from the ground at the same instant. The rock and the ball collide at x = 34.14 m, y = 17.75 m, and t = 2.71 s. If the ball was dropped from a height of h = ...
*February 27, 2012 by please please please helpppp*

**Physics**

Example 1: (Rock A) is thrown against a larger stationary rock(Rock B). considering the following possibilities... 1. Rock A bounces off of Rock B 2. Rock A splits into two pieces off of Rock B 3. Rock A explodes into many pieces off of Rock B What factors are affecting the ...
*November 8, 2013 by Cole*

**PHYSÝCS**

please any one help me for this question The figure shows the paths of a golf ball your friend drops from the window of her apartment and of the rock you throw from the ground at the same instant. The rock and the ball collide at x = 34.14 m, y = 17.75 m, and t = 2.71 s. If ...
*February 27, 2012 by LARA*

**Physics**

A rock is thrown vertically from the edge of a cliff that is 500 ft high. It takes 6.5 seconds for the rock to hit the ground at the base of the cliff. Assume air resistance is negligible. (a) What was the initial velocity (magnitude and direction) of the rock? (b) What was ...
*September 21, 2012 by josephz*

**physics**

Brad tosses a rock straight up at 38.4 m/s. What is the rock's velocity after 2.0 seconds?
*October 21, 2011 by Jinnie*

**physics**

A rock is dropped from rest off a cliff to the surface of a lake which is 6.2 m below. What is the velocity of the rock just as it hits the water?
*September 17, 2012 by Anonymous*

**physics **

Julie throws a rock vertically upward. From a height of 64.0 meters above thehow ground. The initial velocity of the rock is 31.0 meters per second neglect air resistance How long does it take for the rock to hit the ground? What is the velocity of the rock just before it hit ...
*April 1, 2013 by kieshà*

**Calculus Help Please!!! Check **

If a rock is propelled upward from the surface of Mars at a velocity of 93 m/sec, it reaches a height s = 93t – 1.86t^2 after t sec. a. Find the rock’s velocity and acceleration at time t. v'(t)=93-3.72t a''(t)=-3.73 b. How long does it take the rock to reach its highest point...
*April 8, 2014 by Tenshi*

**Calculus Help Please!!! Check **

If a rock is propelled upward from the surface of Mars at a velocity of 93 m/sec, it reaches a height s = 93t – 1.86t^2 after t sec. a. Find the rock’s velocity and acceleration at time t. v'(t)=93-3.72t a''(t)=-3.73 b. How long does it take the rock to reach its highest point...
*April 8, 2014 by Tenshi*

**Physics **

You are standing at the top of a deep, vertical cave and want to determine the depth of the cave. Unfortunately, all you have is a rock and a stopwatch. You drop the rock into the cave and measure the time that passes until you hear the rock hitting the floor of the cave far ...
*September 30, 2012 by Arya *

**Differential Calculus**

a person standing at the edge of a cliff throws a rock directly upward. it observed that 2 seconds later, the rock is it maximum height and that 5 seconds after it reached the highest point, it hits the ground at the base of the cliff. what is the initial velocity of the rock
*April 28, 2015 by rex*

**Writing I**

Label each sentence below. Use S for simple, CD for compound, CX for complex, and CD-CX for compound-complex. 1. Do you know the theory of black holes? 2. Objects in space have gravitational pull, so smaller objects are attracted to larger object. 3. Throw a rock into the air...
*October 30, 2009 by Maria*

**physics**

a 2.50 N rock is thrown down from a cliff at 10.0 m/s. a. what is the velocity after falling 25.0 m? b. velocity as it hits the water 125 m below? c. kinetic energy as it hits the H20?
*November 24, 2013 by carol*

**physics**

A large rock is dropped from a plane flying horizontally at an altitude of 4.00 x 10 ^3 ( to the power of 3) and with a speed of 900km h. a) calculate the distance that the rock will move horizontally before hitting the ground b) find the velocity of the rock just before it ...
*June 11, 2013 by sabine*

**Physics**

In deep space, a small rock orbits an asteroid. The circular, orbit radius is 1037m and the velocity of the rock is 8.02m/s. Find the mass of the asteroid.
*May 26, 2015 by Jenny*

**physics**

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of + 15.5 m/s and measures a time of 13.9 s before the rock returns to his hand. What is the acceleration (magnitude and direction) due...
*June 17, 2013 by louis aaaa*

**physics**

a boy stands on a cliff overlooking a lake below. He throws a rock at an initial velocity of 8.0m/s,at an angle 25 degrees above the horizontal. The lake's surface is 4.5 m lower than the point the rock was released. Find the speed of the rock just before it hits the surface ...
*November 7, 2011 by bec*

**physics**

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of 13.5 m/s and measures a time of 21.8 s before the rock returns to his hand. What is the acceleration due to gravity on this planet? (...
*January 15, 2012 by Jen*

**Physics**

A 14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. Find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earth’s velocity. Earth’s mass is 6.0 × 1024 kg. Show all your work, assuming the...
*January 27, 2012 by Pat*

**physics**

You drop a rock from rest out of a window on the top floor of a building, 50.0 m above the ground. When the rock has fallen 3.80 m, your friend throws a second rock straight down from the same window. You notice that both rocks reach the ground at the exact same time. What was...
*September 17, 2014 by chloe*

**Physics **

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of + 14.2 m/s and measures a time of 22.2 s before the rock returns to his hand. What is the acceleration (magnitude and direction) due ...
*September 6, 2012 by Meghan*

**Physics **

Isaac pushes rock, of a mass of 20kg, if from a cliff and it falls into the lake below. The cliff was 3m above the water. (Assume no air resistance) a. How much time did it take the rock to hit the water? b. What was its velocity when it was half of the distance to the water?
*February 20, 2012 by Hayli*

**Physics**

NEED HELP On a flat battle ground, a catapult is used to launch a rock with a velocity of 25m/s at angle 30 degrees above the horizontal.? Sketch the situation and decompose the initial velocity vector. WHat are the initial values for Vx and Vy? Calculate the maximum height ...
*August 19, 2014 by Jeesha*

**physics**

You drop a rock from rest out of a window on the top floor of a building, 50.0 m above the ground. When the rock has fallen 3.80 m, your friend throws a second rock straight down from the same window. You notice that both rocks reach the ground at the exact same time. What was...
*September 17, 2014 by Anonymous*

**College Physics**

Part A) A 2.2 kg rock is released from rest at the surface of a pond 1.8 m deep. As the rock falls, a constant upward force of 5.0 N is exerted on it by water resistance. Let y=0 be at the bottom of the pond. Calculate the nonconservative work, Wnc , done by water resistance ...
*March 3, 2010 by Kyle*

**College Physics**

A 2.2 kg rock is released from rest at the surface of a pond 1.8 m deep. As the rock falls, a constant upward force of 5.0 N is exerted on it by water resistance. Let y=0 be at the bottom of the pond. Calculate the nonconservative work, Wnc , done by water resistance on the ...
*March 3, 2010 by Kyle*

**physics**

A child wants to throw a rock into a puddle which is 20m away and 20m down a hill. If he can throw the rock at ana ngle of 60, what velocity does he need to release the rock at?
*November 17, 2010 by kristen*

**Physics**

1.You are stuck on a cliff and want to know how far to the bottom. You drop a rock and time how long it takes to hit the ground. If the rock takes 10 seconds to hit the ground how high is the cliff? How fast was the rock going to impact? 2. You throw a plate off your roof with...
*March 22, 2012 by Anonymous*

**Physics**

A rock is dropped into a deep hole and 2.2 s later the sound of striking the bottom is heard. If the speed of sound is 340 m/s, what is the depth of the hole?
*September 5, 2014 by Suzy*

**Physics**

You shoot a rock with a wrist-rocket straight up, it takes 6 seconds for it to come back down (IGNORE THE HEIGHT YOU SHOT IT FROM.) How high did the rock go? what was the rock's speed initially going up (V1)? How fast is it traveling when it hits the ground on the way down?
*October 21, 2011 by Dakota*

**physics**

You attempt to throw the rock across the chasm with a velocity of 35 m/s at and angle of 60 degrees above horizontal. Calculate and label the forward velocity (components) of the rock as it leaves your hand. How long will it take to reach the top of the arc (apogee. How far ...
*October 7, 2014 by david carlos*

**Physics**

A spring is compressed .02m by a 0.5kg rock. The spring and rock are on a frictionless horizontal table. a) If the spring has a spring constant of 5N/m what acceleration will the rock have when released? b) How fast will the rock be moving when it reached the equilibrium point...
*November 30, 2006 by Josiah*

**physics**

A man fires a rock of a slingshot directly upward.The rock has an initial velocity of 15m/s.How long will it take for the rock to return to the level he fired it at?
*April 4, 2013 by Shazz*

**physics**

a man fires a rock of a sling shot upwards. the rock has initial velocity of 15m/s. How long will it take for the rock to reach its highest point??
*October 9, 2014 by lenex purre*

**Physics**

In deep space, a small rock orbits an asteroid. The circular, orbit radius (between their center of masses) is 1037 m and the velocity of the rock is 8.02 m/s. Find the mass (kg) of the asteroid. G=6.67x10^-11 m^3/kgs^2. I got 1.0x10^15 but that is incorrect.
*May 24, 2015 by Sansa Stark*

**College Physics**

Consider a rock thrown off a bridge of height 78.5 m at an angle è = 25° with respect to the horizontal as shown in Figure P4.20. The initial speed of the rock is 15.6 m/s. Find the following quantities: (a) the maximum height reached by the rock (b) the time it takes the rock...
*September 12, 2011 by HELP*

**irsc**

a 10-kg rock and a 20-kg rock are dropped at the same time and experience no significant air resistance. if the 10-kg rock falls with acceleration a, what is the acceleration of the 20-kg rock?
*March 26, 2014 by Anonymous*

**physics**

a man stands on the roof of a building that is 30m tall and throws a rock with a velocity of magnitude of 40m/s at an angle of 33 degress a bove the horizontal. Calculate the following: a.) The maximum height above the roof reached by the rock. b.) The magnitude of the ...
*February 7, 2013 by jm*

**Physics**

A man stands on the roof of a 19.0 m-tall building and throws a rock with a velocity of magnitude 24.0 m/s at an angle of 38.0 degrees above the horizontal. You can ignore air resistance. Calculate the maximum height above the roof reached by the rock. got it.... 11.1 m ...
*September 16, 2006 by Josh*

**physics**

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of +13 m/s and measures a time of 20.5 s before the rock returns to his hand. What is the acceleration (magnitude and direction) due to ...
*July 4, 2010 by Dave*

**physic**

Martha drops a 1 kg rock off the top of Black Oak Canyon which is 100m deep. What is the KE of the rock the instant before it hits bottom? Hint: Conservation of energy states that PE = KE
*February 26, 2013 by POTENTIAL & KINETIC ENERGY PRACTICE*

**Calculus**

Here is my problem that I am trying to work on: A rock is dropped from the top of a 300-ft cliff. It's velocity at time t seconds is v(t0= -32 t feet per second. a.) Find the height of the rock above the ground at time t. b.) How long will the rock take to reach the ground? c...
*May 11, 2009 by Caitlin*

**Physics**

A boy wishes to throw a rock into the river below the cliff where he is standing. The cliff is 50 M high and he can throw with a horizontal velocity of 30 m/s. how long does it take for the rock to reach the water? How far, in the horizontal direction, does the rock land?
*October 30, 2012 by Allison*

**physics**

Consider a rock that is thrown off a bridge of height 27 m at an angle θ = 24° with respect to the horizontal as shown in the figure above. If the initial speed the rock is thrown is 12 m/s, find the following quantities: (a) The time it takes the rock to reach its ...
*September 6, 2010 by frank*

**Physics**

A 0.26 kg rock is thrown vertically upward from the top of a cliff that is 27 m high. When it hits the ground at the base of the cliff the rock has a speed of 24 m/s. (a) Assuming that air resistance can be ignored, find the initial speed of the rock. (b) Find the greatest ...
*March 29, 2010 by Carden*

**physics **

a 20 kg rock is on the edge of a 100 m cliff . the rock falls from the cliff , what is its kinetic energy just before it hits the ground ?
*February 6, 2012 by bob*

**Physics**

A rock is thrown vertically upward with a speed of 11.0 from the roof of a building that is 70.0 above the ground. Assume free fall. In how many seconds after being thrown does the rock strike the ground? What is the speed of the rock just before it strikes the ground? The ...
*September 10, 2006 by JC*

**Physics**

acceleration due to gravity questions A rock is dropped from a height of 7meters a) what is the average velocity of the rock during its fall b) how long does it take the rock to fall
*February 25, 2010 by jake*

**physics**

One day I decide I want to see how high I can throw a rock. I throw a rock straight up in the air and it has a speed of 30 m/s when it leaves my hand. I then realize this was foolish, as I need to get out of the way before the rock comes back down and hits me on the head. How ...
*May 17, 2013 by HELP!!*

**phys**

A rock stuck in the tread of a 56.0--diameter bicycle wheel has a tangential speed of 3.10 . When the brakes are applied, the rock's tangential deceleration is 1.30m/s2 What is the magnitudes of the rock's angular velocity at = 1.70 ?
*May 28, 2012 by keren*

**Physics**

A man stands on the roof of a 15m tall building and throws a rock with a velocity of magnitude 30m/s at an angle of 33deg above the horizontal. Ignore air resistance. Calculate: a) the maximum heigh above the roof reached by the rock b) the magnitude of the velocity of the ...
*September 27, 2011 by Kyle*