Wednesday

February 22, 2017
Number of results: 36,224

**Physics**

A plane flying in a straight line at constant altitude of 2000 m above the ground with a speed of 200m/s drops an object. Explain how the velocity of the object is actually affected by air resistance. Show how the resistivity force of air and velocity of the object varies with...

*March 3, 2014 by Shin*

**PHYSICS**

1. A sound with a frequency of 261.6 Hz travels through water at a speed of 1435 m/s. What is the wavelength of the wave? a. 1.83 x 10 -1 m b. 3.753 x 10 5 m c. 5.486 m d. You cannot tell from the given information 2. A 23.0 kg mass of is accelerated at + 4.50 m/s2. What is ...

*December 21, 2012 by Hayden*

**Physics**

Consider a 4.6 kilogram object moves from the origin always to the right (call that x-axis). Its speed increases uniformly (means constant acceleration) from zero to 0.667 metres/sec. 1.Describe how its velocity changes: initial, final and whether it changes uniformly. 2.The ...

*November 18, 2015 by PhysicsStudents*

**Math**

A rubber ball is thrown straight down from a height of 244 feet at speed of 80 feet per second. If the ball always rebounds with one-fourth of its impact speed, what will be the speed of the ball the third time it hits the ground? My Answer is: 1/4*80=60 1/4*60=45 1/4*45=33.75...

*May 6, 2013 by Zach*

**Physics**

From the top of a tower is an object with mass 25 kg is lowered at constant speed, 4 m / s with a rope to the ground. After 10 seconds of the rope breaks, and the object falls freely. From the moment (the rope breaks) there are 12 seconds to those standing on top of the tower ...

*October 18, 2010 by Oddbjørn*

**physics**

A 80-kg man stands on a bathroom scale inside an elevator. (a) The elevator accelerates upward from rest at a rate of 1.40 m/s2 for 1.50 s. What does the scale read during this 1.50 s interval? N (b) The elevator continues upward at constant velocity for 8.50 s. What does the ...

*October 14, 2014 by Edward*

**math**

If an object is fired upward from the top of a tower at a velocity of 80 feet per second, the tower is 200 ft high, the formula is h(t)=-16t^2+80t+200, t is time h is height, how long after it is fired does the object reach the max height? It is like a quadratic equation

*October 23, 2007 by shila*

**Physics- Object Reaches Maximum Height**

When an object that has been thrown into the air reaches its maximum height, which is true? a. its velocity is zero. b. it is at its terminal velocity. c. it is not in free fall. d. its acceleration is zero.

*November 21, 2016 by MM*

**Physics**

I'm not sure how to do this problem A .40 kg ball is thrown with a speed of 10 s^-1 m at an angle of 30 degrees. (a) What is its speed at its highest point, and (b) how high doe it go? (Use conservation of energy.)

*September 24, 2009 by Physics*

**physics**

a softball is thrown at a speed of 40 miles per hour in a course that makes an angle of 60 degrees with the positive x axis. what is the initial speed in the horizontal direction?

*May 18, 2015 by lee*

**Physics**

A ball is thrown downward from a balcony that is 19.6m above the ground one kid throws downward at 14.7m/s, at the same time another student throws a ball upward from the balcony at the same speed. what is the difference of the time the balls are in the air and what is the ...

*October 1, 2012 by Bear*

**algebra1 HELP PLEASE Thanks you!!**

The function gives the speed in feet per second (ft/s) of a free-falling object after it has fallen x feet (ignoring air resistance). FInd the speed of the object after it has fallen 25 feet. If necessary, round your answer to the nearest tenth.

*July 12, 2013 by lisa*

**PHYSICS**

A baseball is hit with a horizontal speed of 16 m/s and a vertical speed of 16 m/s upward. What are these speeds 5 s later? horizontal speed ?? m/s vertical speed ?? m/s

*March 8, 2008 by jena*

**physics**

a body displaced 12m due to east 5m due to north then 9m vertically upward what is the resultant displacement?solution with complete reason n figure

*August 12, 2011 by armando*

**physics**

a tennis ball is hit vertically upwards with a velocity of 20m/s. what is it's Decelaration as it moves upward? calculate the maximum height reached by the ball.

*April 17, 2015 by Juliet king*

**physics**

the force of kinetic friction between a 60 kg object and a horizontal surface is 50 N. if the initial speed of the object is 25 m/s, what distance will it slide before coming to a stop?

*December 20, 2011 by Dasha*

**PHYSICS**

An object is initially moving in the positive direction of an x-axis with a speed of 2.7 m/s. If the constant acceleration of the object is -0.12 m/s2, what distance will it have traveled when it turns around?

*December 18, 2015 by rebecca*

**Maths nd science**

A ball is thrown vertically upwards.It takes 4 s for the ball to return to the thrower's hand now what is thb maximum height reached by the ball.

*January 17, 2013 by Felicia*

**Science**

An object has a KE of 83.5 J, and a speed of 27.3 m/s. What is the object’s mass?

*October 14, 2014 by Kyla*

**Physics**

Calculate the change in momentum in each of the following situations and state the direction of the change in momentum. a) A 4kg bowling ball strikes a stationary pin head-on at a speed of 3m/s. It continues to move in its original direction, but its speed is reduced to 2m/s. ...

*May 23, 2008 by Alex*

**college**

I am having difficulties doing an eguation for two different times/seconds on an object that is thrown in the air......please help!

*April 4, 2010 by Sue*

**physics**

An object is to be thrown through a window 3.5 m high a distance 7.5 m away. It is launched at an angle 70 degreesabove the horizontal.

*February 9, 2012 by Anonymous*

**Physics**

An object is thrown directly up (positive direction) with a velocity (vo) of 20.0 m/s and do= 0. Determine how long it takes to get to the maximum height of 24.0 m.

*June 14, 2013 by Isis*

**Math**

If you are standing near the edge of the top of a 200 feet building and throw a ball vertically upward it will be modeled by the function s(t)=-16t^2+64t+200 where s(t) is the ball's height above ground in feet and t is seconds after the ball was thrown. A) When does the ball ...

*December 9, 2015 by Anonymous*

**Math**

If you are standing near the edge of the top of a 200 feet building and throw a ball vertically upward it will be modeled by the function s(t)=-16t^2+64t+200 where s(t) is the ball's height above ground in feet and t is seconds after the ball was thrown. A) When does the ball ...

*December 10, 2015 by Anonymous*

**Physics(Simple Harmonic motion and Elasticity)**

A copper rod (length = 2.0 m, radius = 3.0 * 10^-3 m) hangs down from the ceiling. A 9.0-kg object is attached to the lower end of the rod. The rod acts as a “spring,” and the object oscillates vertically with a small amplitude. Ignoring the rod’s mass, find the ...

*April 8, 2013 by Elapid*

**physics**

A rocket blasts off vertically from rest on the launch pad with an upward acceleration of 2.80 . At 30.0 after blastoff, the engines suddenly fail, which means that the force they produce instantly stops.

*October 5, 2011 by mandy*

**physics**

A body thrown upward from ground covers equal distance in 4th and 7th second . With what initial velocity body was projected ?

*May 15, 2016 by omna*

**Dynamics of rigid bodies**

a stone is thrown upward with a velocity of 40m/s.Determine the time of the stone when it is at a height of 10m and is moving downwards.

*January 5, 2017 by Angel*

**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 baseball is thrown upward with a velocity of 15m/s. How fast is it moving after 2 seconds? I have no Idea how to begin and the formula he gave us isn't even related to the question at all. (V=vi+at)

*September 26, 2014 by HelplessFool*

**Physics - Mechanics and Ocsillatory Motion**

The force shown in the figure acts on a 1.7-kg object whose initial speed is 0.44 m/s and initial position is x = 0.27 m. the figure can be found at: [[webassign dot net forwardslash walker forwardslash 07-16 dot gif]] (a) Find the speed of the object when it is at the ...

*October 30, 2010 by Sara*

**Algebra II**

If an object is propelled upward from a height of 16 ft at an initial velocity of 80 feet per sec, the its height after t seconds is given by the equation h=-16t²+80t+16, where h is in feet. after how many seconds will the object reach a height of 116 ft?

*July 3, 2011 by HELP*

**physics**

A body is thrown vertically upwards at an initial velocity of 30m/s. Find the velocity after 2s and the time it takes to reach the maximum height.(TAKE g equal 10m/s2(square).

*May 25, 2016 by josephafful*

**Physics**

Under what condition can a force act on an object and yet do no work on that object? A. The object moves with no acceleration. B. The object does not move. C. The net force on the object is 0. D. The force operates under constant power. E. None of the above, any force on an ...

*February 13, 2009 by Alex*

**algebra1 HELP PLEASE Thanks you!!**

The function f(x)=5 square root of x gives the speed in feet per second (ft/s) of a free-falling object after it has fallen x feet (ignoring air resistance). FInd the speed of the object after it has fallen 25 feet. If necessary, round your answer to the nearest tenth.

*July 12, 2013 by lisa*

**maths-urgently needed**

From the top of a tower the angle of depression of an object on the horizontal ground is found to be 60degree. On descending 20 m vertically downwards from the top of the tower, the angle of depression of the object is found to be 30degree Find the height of the tower.

*February 1, 2013 by Anonymous*

**physics**

One ball is dropped from a cliff. A second ball is thrown down 1.00 s later with an initial speed of 40.0 ft/s. How long after the second ball is thrown will the second ball overtake the first?

*September 30, 2014 by ben*

**physics**

A(n) 0.163 kg baseball is thrown with a speed of 9.37 m/s. It is hit straight back at the pitcher with a final speed of 16.7 m/s. What is the magnitude of the impulse de- livered to the ball? Answer in units of kg · m/s.

*February 27, 2011 by Maria*

**Physics**

A(n) 0.187 kg baseball is thrown with a speed of 29 m/s. It is hit straight back at the pitcher with a final speed of 22.3 m/s. What is the magnitude of the impulse delivered to the ball? Answer in units of kg · m/s

*April 23, 2012 by Sarah*

**Physics (last question)**

A 800 kg projectile is fired vertically upward with an intitial velocity of 50 m/s. Assuming that no friction is present, how high above the ground will the projectile travel?

*November 15, 2007 by Elizabeth*

**physics**

A joggler throws an apple vertically upward just enough to reach the ceiling exactly 4 meters from the jogglers hand . What is the initial velocity of the apple ?

*September 21, 2016 by please help*

**PHYSICS**

If the object travels a distance of 33.0 m in that time determine the following. (a) The acceleration of the object during the 3 second period. [ is the answer 33/9?] m/s2 (b) The maximum speed of the object during the 3 second period. [is the answer 11?] m/s (c) If the mass ...

*October 20, 2009 by Ryan*

**physics**

The figure below gives the speed v versus time t for a 0.510 kg object of radius 5.90 cm that rolls smoothly down a 30° ramp. What is the rotational inertia of the object? 1 kg·m2

*January 5, 2011 by Joey*

**physics**

a cetrifical force of 98N is acted upon a 5kg. ciculating object. If the object is moving at a radius of 1.2m ,what speed is needed to keep it in the cicular motion?

*April 24, 2011 by David*

**AP Physics**

Could you please help me out with the following problems please? If a rocket initially at rest accelerates at a rate of 50 m/s^2 for one minute, its speed will be ? ( I know there are 60 seconds in 1 minute, so would I just use the formula, d=vt, and I would get 3000 m/s) It ...

*September 4, 2007 by Cheyanne*

**Physics**

A ball thrown horizontally from a point 26.0 m above the ground strikes the ground after travelling a horizontal distance of 23.0 m. With what speed was it thrown? Which equation should I use? V= DeltaX / Delta T A= Delta V / Delta T Horizontal motion where X= Xo + Vx(T)

*September 19, 2016 by Bex*

**physics**

A 74-kg fisherman in a 124-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.4 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ...

*October 12, 2012 by Kayla*

**physics**

A ball is thrown straight downward from the surface of the moon. Is the maximum height it reaches less than, equal to, or greater than the maximum height reached by a ball thrown upwards on the earth with the same initial speed? Ignore air resistance in both cases

*September 23, 2012 by tiffany*

**Physics**

A ball is thrown vertically upwards with an initial velocity of 27.0 m/s. Neglecting air resistance, how long is the ball in the air?

*January 23, 2011 by Megan*

**Physics**

A ball is thrown vertically upwards with an initial velocity of 27.0 m/s. Neglecting air resistance, how long is the ball in the air?

*January 23, 2011 by Megan*

**Physcis 1315**

A ball is thrown vertically downward with a velocity of 12m/s How far has the ball fallen 1 s later?. 2s later?

*February 12, 2017 by Anonymous*

**physics**

How high will an object rise if it is projected upward at a 45 degree angle and an initial velocity of 50 m/s?

*November 13, 2012 by Jimmy*

**physics**

How high will an object rise if it is projected upward at a 45 degree angle and an initial velocity of 50 m/s?

*November 13, 2012 by Jimmy*

**physics**

During a snowball ght, your opponent distracts you by throwing a snowball at you with a high arc. She throws snowballs with a speed of 26.5 m/s and the first is thrown at 70.0 degrees. As you are watching the first snowball, she throws a second at a lower angle. (a) If both ...

*August 6, 2011 by waqas*

**Math**

If h(t) represents the height of an object in feet above ground level at time t and h(t) is given by h(t)=−16t^(2)+14t+10 find the height of the object at the time when the speed is zero. The height of the object is h(t)= ___ feet.

*January 28, 2016 by Kyle*

**physics**

A model rocket is launched straight upward with an initial speed of 45.4 m/s. It accelerates with a constant upward acceleration of 2.98 m/s 2 until its engines stop at an altitude of 150 m. What is the maximum height reached by the rocket? The acceleration of gravity is 9.81 ...

*October 2, 2011 by ben*

**physics**

A model rocket is launched straight upward with an initial speed of 51.6 m/s. It accelerates with a constant upward acceleration of 1.96 m/s2 until its engines stop at an altitude of 230 m. What is the maximum height reached by the rocket? The acceleration of gravity is 9.81 m...

*October 11, 2011 by a*

**Physics**

If a projectile is fired straight up at a speed of 10 m/s, the total time to return to its starting position is about ? -Hfinal=hinitial+ vinitial*t -4.9t^2 0=0+10t-4.9t^2 when I solved for t I got .49t.Am I suppose to plug .49t back into the equation? A man leans over the ...

*September 9, 2007 by Jess*

**Physics**

A 26.0 g object moving to the right at 17.0 cm/s overtakes and collides elastically with a 10.0 g object moving in the same direction at 15.0 cm/s. Find the velocity of each object after the collision. a) 26.0 g object b) 10.0 g object

*July 16, 2010 by Daisy*

**Physics**

An egg is thrown from the top edge of a 22.9 m high building down onto an unsuspecting person standing on the ground 6.2 m from the base of the building. If the egg is tossed horizontally, at what speed, in m/s, must the egg be thrown such that it lands on the person?

*April 11, 2016 by Bira*

**Physics**

An egg is thrown from the top edge of a 22.9 m high building down onto an unsuspecting person standing on the ground 6.2 m from the base of the building. If the egg is tossed horizontally, at what speed, in m/s, must the egg be thrown such that it lands on the person?

*April 20, 2016 by Melissa*

**physics**

When it is 152 m above the ground, a rocket traveling vertically upward at a constant 9.50 m/s relative to the ground launches a secondary rocket at a speed of 12.4 m/s at an angle of 50.0 degrees above the horizontal, both quantities being measured by an observer sitting in ...

*November 17, 2010 by alejandrob*

**physics**

A rock is given a KE of 2.00*10^4 J when it is launched vertically upward. If the rock reaches a height of 50m determine the mass of the rock.

*January 6, 2015 by moooose*

**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*

**nature of science**

which of the following best explains velocity? A.the speed & direction of an object in motion C.only the change of direction of an object in motion D.the direction of an object in motion

*November 15, 2013 by science*

**physics**

1) a force of 10 N acts on a 5.0 kg object, initially at rest, for 2.5 s. What is the final speed of the object? 2) a 1500 kh car, is allowed to coast along a level track at a speed of 8.0 m/s. It collides and couples with a 2000-kg truck , initially at rest with brakes ...

*November 29, 2010 by Joceylin*

**science**

hey how u all doin? If a ball is thrown vertically upwards into the air. What is the main energy conversion that takes place as the ball rises towards its maximum height? thanks carl

*December 10, 2008 by carl*

**physics**

a ball of mass 0.1kg is thrown vertically upwards with an initial velocity of 80m/s.calculate the potential energy (I) half way up (ii) at its maximum height.what is the kinetic energy as it leaves the ground

*March 13, 2016 by stephen*

**College Physics**

a horizontal speed of 15.8 m/s and a vertical speed 10.0 m/s upward. What is the vertical speed 1.12 s later?

*September 26, 2010 by J*

**physics**

a stone is projected upward with a speed of 80.0ft/s from a 224 ft tower. find the maximum height and the speed at which it strikes the ground.

*June 21, 2014 by roger*

**physics**

A body moves 6 meters north than 8 meters east than 10 meters vertically upward. What is its resultant displacement from initial position?

*June 13, 2011 by Anant*

**Physics**

A person doing a chin-up weighs 615.4 N, disregarding the weight of the arms. During the ﬁrst 21.0 cm of the lift, each arm exerts an upward force of 435 N on the torso. The acceleration of gravity if 9.81 m/s 2 . If the upward movement starts from rest, what is the ...

*September 28, 2010 by Jim Kirk*

**Physics**

An electron is accelerated by a uniform electric field (1000 V/m) pointing vertically upward. use newton's laws to determine the electron's velocity after it moves .10 cm

*April 25, 2010 by Standard C.*

**physics**

a person throws a stone vertically upward while sitting in a bus moving with constant velocily :) where the stone will fall - a )in his hand b )behind him C )in front of him d )beside him And why

*December 31, 2010 by muhammad usman afridi*

**Science**

A ball is thrown vertically into the air and takes 5s to return to the thrower, from time of projection. What is the time it takes to reach maximum height ?

*January 31, 2011 by Christopher*

**physics**

An object is dropped from ret from a height of 39.4m. What is its average acceleration (assumed to be constant) if it hits the ground with a speed of 1.61m/s? My quesion is, is a not 9.8 since gravity is acting on the object.

*February 2, 2013 by Jane*

**physiscs**

A model rocket is launched straight upward with an initial speed of 53.0 m/s. It acceler- ates with a constant upward acceleration of 3.21 m/s2 until its engines stop at an altitude of 230 m. What is the maximum height reached by the rocket? The acceleration of gravity is 9.81...

*September 29, 2012 by juan*

**Physics**

1. A force F = (3.99xi + 2.86yj) N acts on an object as it moves in the x direction from the origin to x = 4.45 m. Calculate the work done on the object by the force. Attemp: since we only consider x direction i multiplied 3.99 by 4.45 but it didn't work out. 2. A 10.6 kg ...

*October 28, 2010 by Lyn*

**physics**

An object with mass 3.0 kg is attached to a spring with spring stiffness constant k = 300 N/m and is executing simple harmonic motion. When the object is 0.020 m from its equilibrium position, it is moving with a speed of 0.55 m/s. (a) Calculate the amplitude of the motion. m...

*March 7, 2012 by Nicole*

**phy 231**

It takes 23 hours 56 minutes and 4 seconds for the earth to make one revolution (mean sidereal day). a.What is the angular speed of the earth? I got 7.292x10^-5 rad/s b.Assume the earth is spherical. Relative to someone on the rotation axis, what is the linear speed of an ...

*February 20, 2016 by Andrea*

**Algebra II**

A projectile is thrown upward so that its distance above the ground after t sec is given by h(t)=-11t²+264t. After how many seconds does it reach its maximum height?

*July 3, 2011 by HELP*

**Physics**

A rok is thrown 24 meters/sec upward and lands in a 10 meter deep hole. How long is the rock in the air until it reaches the bottom of the hole?

*August 26, 2012 by Alex*

**Physics (Kinematics)**

A ball is thrown 83.3 m upward and then falls back to earth.Neglecting air resistance, how long will it be in the air? The acceleration of gravity is 9.8 m/s2 . Answer in units of s

*October 6, 2012 by Joy*

**physics**

A ball is thrown 107 m upward and then falls back to earth. Neglecting air resistance, how long will it be in the air? The acceleration of gravity is 9.8 m/s2 . Answer in units of s

*October 5, 2013 by rick*

**Science**

A ball is thrown upward at 20 metres per second off the top of a building that is 12 m high. What is the height of the ball above the ground at its highest poin?

*January 29, 2014 by Nthabiseng*

**physics**

A 70-kg fisherman in a 138-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.8 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ...

*March 27, 2012 by Taylor*

**physics**

A 70-kg fisherman in a 138-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.8 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ...

*March 27, 2012 by Taylor*

**physics**

A 74-kg fisherman in a 129-kg boat throws a package of mass m = 15 kg horizontally toward the right with a speed of vi = 4.7 m/s as in the figure below. Neglecting water resistance, and assuming the boat is at rest before the package is thrown, find the velocity of the boat ...

*February 22, 2015 by alba*

**Engineering Science**

A ball is thrown vertically into the air and takes 5s to return to the thrower, from time of projection. What is the time it takes to reach maximum height ?

*January 31, 2011 by Christopher*

**physics**

A projectile is fired at an upward angle of 45 degrees from the top of a 265 m cliff with a speed of 350 m/s. What will be it's speed when it strikes the ground below?

*October 26, 2010 by jessica*

**physics**

true or false If a net force acts on an object, the object's speed will change. An object's velocity will change if a net force acts on the object. If two object have the same acceleration, they are under the influence of equal forces. The net force which acts on an object ...

*October 4, 2010 by molly*

**physics**

a ball is thrown at an initial angle of 37 and initail velocity of 23.0 m/s reaches a maximum height h, as shwon in the Figure. With what initial speed must a ball be thrown straight up to reach the same maximum height h?

*January 3, 2011 by Anonymous*

**Physics**

A ball thrown by a boy in the street is caught 5 s later by another boy on the balcony of the house 10 m away and 3 m above the street level. What is the initial speed of the ball? What is the angle above the horizontal at which it was thrown?

*August 25, 2014 by Kadu*

**Physical Science**

Can someone please check these answers for me? Write T for True or F for False for each statement: 1.Kinetic energy is the energy of motion - T 2.Kinetic energy doesn't depend on an object's direction. - T 3.When an object stops moving, its kinetic energy is zero. - T 4.As the...

*April 20, 2009 by mysterychicken*

**physics**

You are designing a game for small children and want to see if the ball’s maximum speed is sufficient to require the use of goggles. In your game, a 15.0-g ball is to be shot from a spring gun whose spring has a force constant of 600 N/m. The spring will be compressed 5.00 ...

*March 4, 2010 by bill*

**Physics**

A 6.2 kg model rocket is traveling horizontally and due south with a speed of 20.3 m/s when it explodes into two pieces. The velocity of one piece, with a mass of 1.6 kg, is v1 = (-12 m/s)i + (30 m/s)j + (15 m/s)k, with i pointing due east, j pointing due north, and k pointing...

*February 24, 2014 by Nat*

**Physics**

A helicopter is lifting off from the ground and is moving vertically upward. The graph shows its vertical velocity vy versus time. How high is the helicopter after 7 s have elapsed?

*September 26, 2010 by Lily*

**Physics**

A helicopter is lifting off from the ground and is moving vertically upward. The graph shows its vertical velocity vy versus time. How high is the helicopter after 12.0 s have elapsed?

*September 5, 2011 by Kyle*