Sunday

April 19, 2015

April 19, 2015

Number of results: 31,086

**Physics help please!**

While visiting Planet Physics, you toss a rock straight up at 13.6 m/s and catch it 3.50 s later. While you visit the surface, your cruise ship orbits at an altitude equal to the planet's radius every 340.0 minutes. What is the mass (in kg) of the planet?
*November 30, 2011 by ....*

**Physics**

How high will a 1.60-{\rm kg} rock go if thrown straight up by someone who does 75.0 J of work on it? Neglect air resistance.
*September 27, 2011 by Frank*

**physics**

Heather and Jerry are standing on a bridge 53m above a river. Heather throws a rock straight down with a speed of 12m/s . Jerry, at exactly the same instant of time, throws a rock straight up with the same speed. Ignore air resistance. How much time elapses between the first ...
*October 9, 2014 by Haley*

**Science**

1.) Robin hood shoots an arrow up in the night sky. What is the acceleration at the very top of its path? 2.) Juan's car has an acceleration = -2.76m/s^2 and a velocity = 43m/s. Is he slowing down or speeding up?
*October 20, 2014 by Candy*

**math**

a fair coin is tossed in the air 4 times. if the coin lands heads up the first three tosses, what is the probability the coin will land heads up the fourth toss? I think it is 1/2 because the coin has 2 sides and 50% it will land on heads. My friend thinks it is 1/16, since ...
*May 12, 2013 by Ellie*

**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*

**Angular Acceleration**

A rock stuck in the tread of a 50.0 cm diameter bicycle wheel has a tangential speed of 3.5 0m/s . When the brakes are applied, the rock's tangential deceleration is 1.40 m/s^2 . What is the magnitudes of the rock's angular acceleration at = 1.70 ?
*February 14, 2012 by MaxX*

**physics**

A rock is shot vertically upward from the edge of the top of a tall building.The rock reaches its maximum height above the top of the building 1.90 s after being shot. Then, after barely missing the edge of the building as it falls downward, the rock strikes the ground 9.00 s ...
*September 12, 2013 by kristy*

**physics**

A person walks the path shown below. The total trip consists of four straight-line paths. Path 1 is 80.0 m due east. Path 2 is 250.0 m due south. Path 3 is 130.0 m 30.0° south of west. Path 4 is 190.0 m 60.0° north of west. At the end of the walk, what is the person's ...
*December 13, 2012 by Anonymous*

**science help!!!!!!!!!**

You are creating a carbon cycle poster. In which way would you draw the arrows to show the movement of carbon through the process of resperation? A.from the rock to the air B.from the rock to the grass C.from the air to the wolf D. From the wolf to the air Is the answer D?
*November 7, 2014 by butterfly*

**physics**

How high will a 1.95 rock go from the point of release if thrown straight up by someone who does 66.5 of work on it? Neglect air resistance.
*June 25, 2012 by Anonymous*

**Physics**

Consider an object on a straight-line path undergoing constant acceleration. Can you get the object to change direction while still experiencing constant acceleration?
*March 13, 2012 by Anonymous*

**math **

a rock is thrown straight up in the air from an initial height of ho, in metres, with the initial velocity vo, in metres per second. The height in metres above the ground after t seconds is given by h(t) = -4.9t^2 + vo + ho. Find an expression for the time it takes the rock to...
*November 29, 2013 by Kp*

**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**

Upon spotting an insect on a twig overhanging water, an archer fish squirts water drops at the insect to knock it into the water. Although the insect is at distance d from the fish along a straight-line path at angle $ (as in the figure here), a drop must be launched at a ...
*September 13, 2010 by Antonio*

**physics**

A record of travel along a straight path is as follows: 1. Start from rest with constant acceleration of 2.59 m/s2 for 19.0 s. 2. Maintain a constant velocity for the next 2.15 min. 3. Apply a constant negative acceleration of −9.08 m/s2 for 5.42 s. (a) What was the ...
*September 10, 2014 by Armando*

**Physics please help**

While visiting Planet Physics, you toss a rock straight up at 13.6 m/s and catch it 3.50 s later. While you visit the surface, your cruise ship orbits at an altitude equal to the planet's radius every 340.0 minutes. What is the radius (in m) of the planet? What is the mass (in...
*November 27, 2011 by Anonymous*

**Physics help please!**

While visiting Planet Physics, you toss a rock straight up at 13.6 m/s and catch it 3.50 s later. While you visit the surface, your cruise ship orbits at an altitude equal to the planet's radius every 340.0 minutes. What is the radius (in m) of the planet? What is the mass (in...
*November 29, 2011 by ...*

**Physics**

A record of travel along a straight path is as follows: (a) Start from rest with constant acceleration of 3.51 m/s2 for 17.8 s; (b) Constant velocity of 62.478 m/s for the next 0.946 min; (c) Constant negative acceleration of −10.9 m/s2 for 3.89 s. What was the total ...
*September 11, 2011 by Margo*

**Physics**

A record of travel along a straight path is as follows: (a) Start from rest with constant acceleration of 3.07 m/s2 for 16.5 s; (b) Constant velocity of 50.655 m/s for the next 0.767 min; (c) Constant negative acceleration of −9.49 m/s2 for 5.89 s. What was the total ...
*October 6, 2014 by Anonymous*

**Physics**

A person walks the path shown below. The total trip consists of four straight-line paths. Path 1 is 30.0 m due east. Path 2 is 200.0 m due south. Path 3 is 140.0 m 30.0° south of west. Path 4 is 170.0 m 60.0° north of west. At the end of the walk, what is the person's ...
*November 1, 2012 by Mel*

**algebra**

Rock is thrown from the top of a building. The formula h=-16t+234 describes the height of the rock, h in feet, t seconds after the rock is thrown. how long after the rock is thrown does it hit the ground?
*December 13, 2014 by MB*

**Math**

A landscaper is designing a garden with hedges through which a straight path will lead from the exterior of the garden to the interior. If the polar coordinates of the endpoints of the path are (20, 90°) and (10, 150°), where r is measured in feet, what is the equation for the...
*September 6, 2011 by Andrew*

**science**

A rock is thrown vertically upward with an initial speed of 100 ft/s. At the same instant another rock is thrown vertically downward from the top of a 280 ft cliff with an initial speed of 40 ft/s. Neglecting air friction,
*January 9, 2013 by Anonymous*

**PHYSICS**

A rock is dropped from rest into a well. The sound of the splash is heard 2.40 s after the rock is released from rest. (a) How far below the top of the well is the surface of the water? The speed of sound in air (at the ambient temperature) is 336 m/s. (3p) (b) What If? If the...
*September 24, 2010 by JULIET*

**Physics**

A person walks the path shown below. The total trip consists of four straight-line paths. Path 1 is 40.0 m due east. Path 2 is 170.0 m due south. Path 3 is 120.0 m 30.0° south of west. Path 4 is 190.0 m 60.0° north of west. At the end of the walk, what is the person's ...
*September 17, 2012 by David*

**physics**

A 0.5 kg rock is projected from the edge of the top of a building with an initial velocity of 9.66 m/s at an angle of 41 degrees. The building is 10.1 m in height. At what horizontal distance, x, from the base of the building will the rock strike the ground? Assume the ground ...
*January 3, 2015 by Kimberly*

**physics**

please tell me if these are correct A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0 deg above the horizontal. What is teh magnitude of her horizontal displacement? (Assume no air resistance and that Ay= -g = -9.81 m/s^2) i got 9.2 m ...
*February 15, 2009 by y912f*

**physics**

A child standing on the edge of a sheer cliff wall throws a rock down towards the ground below. The rock is thrown 67° below the horizontal at a speed of 22 m/s & lands 43 m from the base of the cliff wall. Ignore air drag. A.) Determine how long the rock was in the air. s B...
*September 6, 2012 by Cindy*

**Physics **

Four rocks are thrown horizontally from a building, with varying speeds and from various floors. Rock 1 lands a distance r away from the building, rock 2 lands 2r away from the building, rock 3 lands at distance 3r, and rock 4 at 4r. Ignore air resistance. Drag the rocks into ...
*July 5, 2014 by Anonymous*

**Physics**

Ball A is thrown straight down off the top of a tall building with an initial velocity of 20m/s. Ball b is thrown straight up from the top of the same building with initial velocity of 20 m/s. Which ball, if either, experiences the greater acceleration after leaving the ...
*February 7, 2014 by Chris*

**physics**

a 100 kg boulder is placed under the surface of water. its volume is 0.5 x 10^5 cm^3. what is the weight of the rock while under water; compare that to the weight of the rock in air (sitting on the ground) i just found the weight of the rock in air by multiplying 100 kg by 9.8...
*March 16, 2010 by john*

**physics**

A rock is thrown upwards from the top of a 100m cliff, on the way down the rock misses the edge of the cliff and continues falling to the ground. What is the distance that the rock travelled?
*November 4, 2012 by dhkk*

**Physics**

Two grenades, A and B, are thrown horizontally with different speeds from the top of a cliff 70 m high. The speed of A is 2.50 m/s and the speed of B is 3.40 m/s. Both grenades remain in air for 3.77 s. Assume that the acceleration due to gravity is 9.86 m/s^2. What is the ...
*September 21, 2009 by Willie*

**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**

ignoring air resistance, describe how an object would fall to the ground using the words velocity and acceleration for a ball that is thrown straight up: a.) the velocity is __on the way up (increasing, decreasing, constant, zero) b.)the velocity is __at the very top (...
*October 9, 2012 by Anita*

**physics**

Mrs bautista accelerates her bicycle uniformly along a straight path from 10.5 m/s to rest in 5.2s. A. What is her acceleration? B. What is her displacement during this time interval?
*July 15, 2014 by Alyssa ponce*

**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 1**

A rock is thrown straight upward with an initial velocity of 9.6 m/s in a location where the acceleration due to gravity has a magnitude of 9.81 m/s2. To what height does it rise? Help meh please.
*September 29, 2010 by Aisumi*

**Physics**

A 5.00×10^5-kg rocket is accelerating straight up. Its engines produce 1.250×10^7 N of thrust, and air resistance is 4.50×10^6 N. What is the rocket’s acceleration? I just need the formula for finding the acceleration.
*October 1, 2014 by Kyle*

**Calculus**

A rock is dropped from the top of a 400-foot-tall building. Its distance s (in feet) from the top of the building after t seconds is s(t) = 16t^2. How many seconds will it take the rock to hit the ground?
*June 8, 2014 by Syed*

**Physics**

A 1.1 kg lizard lies on a flat rock tilted. A person decides to tilt the rock hoping that the lizard falls off. The rock is tilted at an angle of 15 degrees with respect to the horizontal. The coefficient between the rock and the lizard is .16. What is the acceleration of the ...
*November 19, 2012 by Elle*

**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**

A rock stuck in the tread of a 50.0 cm diameter bicycle wheel has a tangential speed of 3.5 0m/s . When the brakes are applied, the rock's tangential deceleration is 1.40 m/s^2 . What is the magnitudes of the rock's angular acceleration at = 1.70 ?
*February 14, 2012 by Max*

**Physics**

A rock stuck in the tread of a 50.0 cm diameter bicycle wheel has a tangential speed of 3.5 0m/s . When the brakes are applied, the rock's tangential deceleration is 1.40 m/s^2 . What is the magnitudes of the rock's angular acceleration at = 1.70 ?
*February 14, 2012 by Max*

**Physics**

When a drag strip vehicle reaches a velocity of 60 m/s, it begins a negative acceleration by releasing a drag chute and applying its brakes. While reducing its velocity back to zero, its acceleration along a straight line path is a constant -7.5 m/s2. What displacement does it...
*December 5, 2010 by Jesse*

**physics**

A straight ladder is leaning against the wall of a house. The ladder has rails 4.50 m long, joined by rungs 0.470 m long. Its bottom end is on solid but sloping ground so that the top of the ladder is 0.780 m to the left of where it should be, and the ladder is unsafe to climb...
*April 4, 2011 by Bob*

**physics**

Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of the rock is to (1pts)
*June 12, 2013 by Anonymous*

**physics**

A rock stuck in the tread of a 57.0 cm diameter bicycle wheel has a tangential speed of 3.00 m/s. When the brakes are applied, the rock's tangential deceleration is 1.40 m/s^2. At what time is the magnitude of the rock's acceleration equal to g?
*November 27, 2010 by skywalker*

**7th grade science **

Q: An igneous intrusion cuts through three layers of sedimentary rock. which rock is the youngest? and why? A: A) the igneous intrusion B) the top layer of sedimentary rock C) the middle layer of sedimentary rock D) the bottom layer of sedimentary rock
*November 18, 2012 by Kate*

**Physics**

If you throw a ball into the air at some angle with respect to the horizontal, which of the following statements about the ball is true? The acceleration is zero at the top of the motion The horizontal component of the velocity is zero at the top of the motion The velocity is ...
*January 27, 2015 by Chris*

**physics**

A quarterback threw a football at 27 m/s at a certain angle above the horizontal. If it took the ball 3.3 s to reach the top of its path, how long was it in the air? s
*January 13, 2015 by mathew*

**Physics**

The acceleration of gravity at the surface of a newly discovered planet is 5.2 m/s^2. An astronaut throws a rock straight up at 10.5 m/s on this planet. How high will it go?
*September 25, 2012 by REALLY NEED HELP*

**Physics**

Using energy considerations and neglecting air resistance, calculate how far a rock will rise above its point of release if it is tossed straight up with an initial speed of 10m/sec. Using energy considerations and neglecting air resistance, calculate how far a rock will rise ...
*January 29, 2011 by Anonymous*

**physics**

To measure the height of a tree, you throw a rock directly upward, with a speed just fast enough that the rock brushes against the uppermost leaves and then falls back to the ground. If the rock is in the air for 2.1 s, how tall is the tree?
*September 7, 2010 by frank*

**physics**

To measure the height of a tree, you throw a rock directly upward, with a speed just fast enough that the rock brushes against the uppermost leaves and then falls back to the ground. If the rock is in the air for 2.1 s, how tall is the tree?
*September 7, 2010 by frank*

**physics**

A rock is thrown horizontally from a bridge with a speed of 30.3 m/s. If the rock is 27.2 meters above the river at the moment of release, a)how long the rock is in the air? b)what is the horizontal distance to the point of impact from the point of release? c)what is the speed...
*November 3, 2010 by Nathaniel*

**Physics**

A 3 kg ball is dropped from the top of a cliff. At the same time, a 9 kg ball is fired straight down from the top of the cliff. Ignoring air resistance, what can we say about their accelerations after being released?
*November 4, 2010 by Zaphod*

**Physics**

a small rock with mass 0.20 kg is released from rest at point A which is at the top edge of a large, hemispherical bowl with radius R = .5m. assume that the size of the rock is small compared to R, so that the rock can be treated as a particle, and assume that the rock slides ...
*October 23, 2012 by Frankie*

**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 *

**Physics**

The acceleration of gravity at the surface of a newly discovered planet is 5.2 m/s^2. An astronaut throws a rock straight up at 10.5 m/s on this planet. How high will it go? Please help!!!
*September 25, 2012 by Savannah*

**Physics**

display.cgi?id=1225682948 I'm still confused about how you got the (1/8)kx^2 and how to find the weight's maximum height at the top of its path through the air.
*November 3, 2008 by Bertrand*

**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**

A straight ladder is leaning against the wall of a house. The ladder has rails 4.80 m long, joined by rungs 5.100 m long. Its bottom end is on solid but sloping ground so that the top of the ladder is 3.100 m to the left of where it should be, and the ladder is unsafe to climb...
*March 14, 2011 by kia*

**physics homework**

You throw a 20 N rock into the air from ground level and observe that when it is 1 5.0 M high, it is traveling upward at 25.0 m/s. Use the work energy principle to find (a) the rock’s speed just as it left the ground and (b) the maximum height the rock will reach.
*February 23, 2013 by samantha*

**Physics-check answer please (multiple choice)**

1. A 2.5 kg mass at rest on a horizontal surface is acted upon by an applied horizontal force of 150 N. A frictional force of 100 N acts on the mass. How much work is done on the mass? my answer: would the work be 0? 2. When a rock is thrown straight up in the air, after it ...
*February 24, 2014 by Lisa*

**Physics**

A rock is thrown straight upward with an initial velocity of 9.6 m/s in a location where the acceleration due to gravity ahs a magnitude of 9.81 m/s^2. To what height does it rise? please walk me through this problem:)
*February 7, 2009 by y912f*

**physics**

A rock is thrown straight upward with an initial velocity of 9.6 m/s in a location where the acceleration due to gravity has a magnitude of 9.81 m/s^2. To what height does it rise? i got 4.7 can you please show me how to solve for this last one
*February 17, 2009 by y912f*

**physics**

A 0.67 kg rock is projected from the edge of the top of a building with an initial velocity of 11.6 m/s at an angle 52 ◦ above the horizontal. Due to gravity, the rock strikes the ground at a horizontal distance of 19.5 m from the base of the building. How tall is the ...
*September 2, 2012 by Noah*

**Physics**

A 0.54 kg rock is projected from the edge of the top of a building with an initial velocity of 13.8 m/s at an angle 59◦ above the horizontal.Due to gravity, the rock strikes the ground at a horizontal distance of 20.3 m from the base of the building.How tall is the ...
*November 29, 2012 by Big Poppa Smurf*

**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*

**Geometry**

A streetlight is mounted on top of a 15 ft. pole. A 6-ft tal man walks away from the pole along straight path. How long is his shadow when he is 40 ft from the pole?
*January 8, 2012 by M.C.*

**Calculus**

The acceleration due to gravity near the surface of Mars is 3.72ms^-2 . A rock is thrown straight up from the surface with an initial velocity of 23ms^-2 . How high does it go?
*May 13, 2013 by Grant*

**Physics**

A rock of mass m = 1.8 kg is tied to a string of length L = 2.4 m and is twirled in a vertical circle as shown in the figure below. The speed v of the rock is constant; that is, it is the same at the top and the bottom of the circle. If the tension in the string is zero when ...
*October 26, 2011 by Freud*

**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 Find mass and radius of planet.**

While visiting Planet Physics, you toss a rock straight up at 15 m/s and catch it 2.4 s later. While you visit the surface, your cruise ship orbits at an altitude equal to the planet's radius every 240 min. What is the mass of Planet Physics? What is the radius of Planet Physics?
*April 5, 2010 by Mike*

**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*

**General Science**

A power boat accelerates along a straight path from 0km/h in 10.0s.Find the average acceleration of the boat in meters per second.
*January 30, 2013 by K-Lynn*

**Physics **

A rock of a mass 0.2kg is attatched to a 0.75m long string and swung in a vertical plane. What is the slowest speed that the rock can travel and still maintain a circular path. so, i started with the following equation: Fc= mv2/r but where do i go from there to solve for v(...
*October 24, 2009 by NeedHelp!*

**Physics **

A rock of a mass 0.2kg is attatched to a 0.75m long string and swung in a vertical plane. What is the slowest speed that the rock can travel and still maintain a circular path. so, i started with the following equation: Fc= mv2/r but where do i go from there to solve for v (...
*October 24, 2009 by Lila*

**physics**

A rocket, initially at rest on the ground, accelerates straight upward from rest with constant acceleration 49.0 . The acceleration period lasts for time 10.0 until the fuel is exhausted. After that, the rocket is in free fall. What's the max height? Ignore air resistance and ...
*September 28, 2011 by Uzz*

**physics**

A rock is dropped. How fast will the 5.0 kg rock be traveling in 4.0s if a 5.o N force of air resistance acts on it?
*December 16, 2010 by Nate*

**Science**

When a football is kicked into the air, it has a velocity of 32m/s at an angle of 25º. At the very top of the ball’s path, what is it's vertical velocity?
*March 16, 2015 by Brenna*

**physics**

A record of travel along a straight path is as follows: 1. Start from rest with constant acceleration of 2.77 m/s^2 for 15 s 2. Constant velocity for the next 2.05 min 3. Constant negative acceleration -9.47 m/s^2 for 4.39 s. (a) What was the total displacement for complete ...
*September 6, 2007 by Anonymous*

**physics**

A 8kg ball is thrown up with an initial speed of 20m/s. Suppose there is a constant air resistence of 30N opposing the motion during its entire up and down path. How long will it take to get to the highest point in its path? how high is the highest point? How much work was ...
*December 20, 2010 by dipset*

**physics**

a rock is dropped from the top of diving platform into the swimming pool below. will the distance traveled by the rock in a 0.1 second interval near the top of the flights be the same as the distance covered in a 1.1 second interval just before it hits the water? Explain?
*February 24, 2011 by jb*

**Physics**

From the edge of a 25 m building, a student threw s rock up 35 m/s and it landed on the ground. How long was the rock in the air?
*November 12, 2010 by Marie*

**physics**

what speed must you toss a ball straight up so it takes 2s to return to you
*October 25, 2012 by manuel*

**Physics**

A boy jumps from rest, straight down from the top of a cliff. He falls halfway down to the water below in 0.620 s. How much time passes during his entire trip from the top down to the water? Ignore air resistance.
*September 8, 2014 by Hoku*

**Physics**

bob drop a rock from a height of 4.5 m. (the acceleration due to gravity is 9.8 m/s^2) 1.at s the initial speed of the rock 2. how long is the rock falling before it hits the ground c. what is the final speed of the rock? [I have trouble with c) My work: a) v1 =0m/s b) v1t +1/...
*December 1, 2014 by Ash*

**earth**

#40 which type of rock is a result of a rock changing by heat and pressure? a. metamorphic rock b. igneous rock c. sedimentary rock d. metal ores
*January 13, 2013 by ?*

**Physics -- check answers**

1. In moving an object of mass 10 kg through a distance of 8.0 m, 40 J of work is done. The average force exerted is? my answer: 320N 2. What is the kinetic energy of a 20 kg object moving at a speed of 10 m/s? my answer: 1000J 3. the gravitational potential energy of a bird ...
*February 23, 2014 by Lisa*

**12 Math**

Graph the results of a coin toss: Toss Coins 0 20 1 12 2 5 3 1 4 0 State an equation that best fits the results (use n to represent the number of the toss). What physical phenomenon does this model? I was able to graph this, I just do not understand how to write the equation, ...
*November 10, 2010 by Ali*

**Physics**

A boy kicks a rock off a cliff with a speed of 19.4 m/s at an angle of 52.5° above the horizontal. The rock hits the ground 5.41 s after it was kicked. a) How high is the cliff? (I found the height to be 60.3 m) b) What is the speed of the rock right before it hits the ground...
*February 5, 2011 by Anonymous*

**Physics -- check answers please**

1. In moving an object of mass 10 kg through a distance of 8.0 m, 40 J of work is done. The average force exerted is? my answer: 320N 2. What is the kinetic energy of a 20 kg object moving at a speed of 10 m/s? my answer: 1000J 3. the gravitational potential energy of a bird ...
*February 23, 2014 by Lisa*

**physics**

A 4.2 kg rock is initially at rest at the top of a cliﬀ. Assume that the rock falls into the sea at the foot of the cliﬀ and that its kinetic energy is transferred entirely to the water. How high is the cliﬀ if the temperature of 1.5 kg of water is raised ...
*February 13, 2012 by Anonymous*

**Physics**

Top fuel drag racer can reach the maximum speed of 304 mph at the end of the 1/4-mile (402 m) racetrack. (a) Assuming that the acceleration is constant during the race, calculate the average value of the acceleration of the top fuel car. (b) What is the ratio of that ...
*September 1, 2011 by Logan*

**Physics Help**

A crane is used to lift air conditioning units to the top of a 5-story building. Each story is 3.5 m high. The crane accelerates the units while lifting the units past the first story and then lifts them at a constant velocity past the second through fourth stories. it hen ...
*September 14, 2014 by Anonymous*

**Physics**

A rock is thrown vertically with a velocity of 21 m/s from the edge of a bridge 41 m above the river. How long does the rock stay in the air? V = 21 m/s d = 41 m a = -9.80 m/s^2 t = ?
*September 4, 2007 by Anon*