A boy is standing on an elevator which is traveling downward with a constant velocity of 30 meters per second. The boy throws a ball vertically upward with a velocity of 10 meters per second relative to the elevator. What is the velocity of the ball, MAGNITUDE AND DIRECTION, relative to the elevator shaft the instant the boy releases the ball?

A boy is standing on an elevator which is traveling downward with a constant velocity of 30 meters per second. The boy throws a ball vertically upward with a velocity of 10 meters per second relative to the elevator. What is the velocity of the ball, MAGNITUDE AND DIRECTION, relative to the elevator shaft the instant the boy releases the ball?
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ANSWER: 20 METERS PER SECOND DOWN
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A helicopter is ascending vertically with a constant speed of 6 meters per second relative to the ground. At the instant the helicopter is 60 meters above the ground it releases a package. What is the magnitude and direction of the velocity of the package, relative to the ground, the instant the package is released by the helicopter?

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Description : A boy throws a ball vertically upward with a velocity of 6 meters per second. How long does it take the ball to return to the boy's hand?

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An object is projected vertically upward near the surface of the earth. At the very top of its path, the object's velocity is zero, and its acceleration is: w) 0 x) 9.8 meters per second squared DOWNWARD y) 9.8 meters per second squared UPWARD z) depends on the mass of the object

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Last Answer : ANSWER: X -- 9.8 METERS PER SECOND SQUARED DOWNWARD

A girl throws a 2 kilogram rock vertically upward. It reaches a maximum height of 5 meters. What is the kinetic energy of the rock the instant it leaves the girl's hand?

Description : A girl throws a 2 kilogram rock vertically upward. It reaches a maximum height of 5 meters. What is the kinetic energy of the rock the instant it leaves the girl's hand?

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A car traveling at a constant velocity of 20 meters per second passes a second car which is initially at rest. The car which was at rest starts accelerating at 10 meters per second squared the instant it is passed by the first car. They will meet again in: w) 2 seconds x) 4 seconds y) 6 seconds z) 8 seconds

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A girl throws a ball vertically upward, what is the MOMENTUM of the ball at its highest point?

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A girl throws a 0.1 kilogram ball at a wall. The ball hits the wall perpendicularly with a velocity of 5 meters per second and then bounces straight back with a velocity of 4 meters per second. The change in the momentum of the ball is: w) 0.1 kilogram-meters per second x) 0.4 kilogram-meters per second y) 0.5 kilogram-meters per second z) 0.9 kilogram-meters per second

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A particle is thrown vertically upward. When it reaches the highest point, it has – (1) a downward acceleration (2) an upward acceleration (3) a downward velocity (4) a horizontal velocity

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A particle is thrown vertically upward. When it reaches the highest point, it has (1) a downward acceleration (2) an upward acceleration (3) a downward velocity (4) a horizontal velocity

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Last Answer : a downward acceleration

A ball leaves a girl's hand with an upward velocity of 6 meters per second. What is the maximum height of the ball above the girl's hand?

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If a boy sitting in a train, which is moving at a constant velocity, throws a ball straight up into the air, the ball will – (1) Fall in front of him (2) Fall behind him (3) Fall into his hand (4) None of the above

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If a boy sitting in a train, which is moving at a constant velocity, throws a ball straight up into the air, the ball will (1) fall in front of him (2) fall behind him (3) fall into his hand (4) None of the above

Description : If a boy sitting in a train, which is moving at a constant velocity, throws a ball straight up into the air, the ball will (1) fall in front of him (2) fall behind him (3) fall into his hand (4) None of the above

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A ball is thrown vertically upwards from the ground with a speed of 80 feet/second. In the English system of units, what is the magnitude and direction of the acceleration of the ball?

Description : A ball is thrown vertically upwards from the ground with a speed of 80 feet/second. In the English system of units, what is the magnitude and direction of the acceleration of the ball? 

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A man standing on a edge of a cliff throws a stone vertically upwards with a certain speed. He then throws another stone downwards with the same speed. Find the ratio of the speeds of the two stones when they hit the ground. (1) 1 : 1 (2) 1 : 2 (3) 1 : 4 (4) Cannot be found from the given information.

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A boy sitting in an open car moving with the constant speed throws a ball straight up into the air. (1) The ball falls – (2) Behind him (3) In front of him (4) Into his hand

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Last Answer : behind him

What is the DeBroglie wavelength of a 1,200 kilogram corvette traveling at a rate of 25 meters per second? Planck's constant is equal to 6.62 x 10-34 Joule-seconds. w) 5.3 x 10-32 meters x) 5.9 x 10-34 meters y) 2.1 x 10-38 meters z) 1.6 x 10-40 meters

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Last Answer : ANSWER: Y -- 2.1 x 10-38 METERS

An exceptional demand curve is one that moves - (1) upward to the right (2) downward to the right (3) horizontally (4) vertically

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Pick out the correct statement pertaining to Venturimeter. (A) A Venturimeter with a fixed pressure drop discharges more, when the flow is vertically downward, than when the flow is vertically upward (B) The co-efficient of contraction of a Venturimeter is always unity (C) For a fixed pressure drop, the discharge of a gas through a Venturimeter is greater, when compressibility is taken into account, than when it is neglected (D) None of these

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An exceptional demand curve is one that moves (1) upward to the right (2) downward to the right (3) horizontally (4) vertically

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At time t=0, a body has a velocity of 5 meters per second, EASTWARD; at time t=2 seconds, its velocity is 7 meters per second WESTWARD. What is the MAGNITUDE of the body's average acceleration?

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A person weighs more in a lift, which is (a) moving up with a constant velocity (b) moving down with a constant velocity (c) accelerating upward (d) accelerating downward

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Last Answer : Ans:(c)

A stone is thrown vertically upwards from the ground with a velocity 15 m/s. At the same instant a ball is dropped from a point directly

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Archimedes principle states that  a. when a body is inversed in a fluid, the fluid exerts a downward force on the body whose magnitude is equal to the weight of the displaced fluid  b. when a body is inversed in a fluid, the fluid exerts a upward force on the body whose magnitude is equal to the weight of the displaced fluid.  c. when a body is inversed in a fluid, the fluid exerts a downward force on the body whose magnitude is greater than the weight of the displaced fluid.  d. when a body is inversed in a fluid, the fluid exerts a downward force on the body whose magnitude is lower than the weight of the displaced fluid.

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Last Answer : when a body is inversed in a fluid, the fluid exerts a upward force on the body whose magnitude is equal to the weight of the displaced fluid.

A man is standing on a weighing machine in a lift which is moving. The weighing machine will show minimum reading when, the lift is moving A. In a free fall due to failure of the lift mechanism B. Upward with uniform acceleration C. Downward with uniform acceleration D. Upward with uniform speed

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Last Answer : ANSWER: A

A man is standing on a weighing machine in a lift which is moving. The weighing machine will slow MINIMUM reading when, the lift is moving? A. Upward with uniform speed B. Downward with uniform acceleration C. In a free fall due to failure of the lift mechanism (Answer) D. None of these

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A ball is thrown upwards with an initial velocity of 5 meters per second. How many seconds will it take to reach maximum height? w) 0.5 seconds x) 1 second y) 1.5 seconds z) 2 seconds

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Last Answer : ANSWER: W -- 0.5 SECONDS

What is the initial velocity of an object if it is moving 10 meters per second after 2 seconds with a constant acceleration of 4 meters per second squared?

Description : What is the initial velocity of an object if it is moving 10 meters per second after 2 seconds with a constant acceleration of 4 meters per second squared?

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A ball falling vertically from rest for 3 seconds travels very nearly: w) 14.7 meters x) 29.4 meters y) 44.1 meters z) 88.2 meters

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An 8 kilogram mass resting on a frictionless horizontal surface is attached to a spring with a force constant of 50 Newtons per meter. If the velocity of the mass through the equilibrium position is 5 meters per second, what is the mass's maximum displacement from equilibrium?

Description : An 8 kilogram mass resting on a frictionless horizontal surface is attached to a spring with a force constant of 50 Newtons per meter. If the velocity of the mass through the equilibrium position is 5 meters per second, what is the mass's maximum displacement from equilibrium?

Last Answer : ANSWER: 2 METERS

A man in a train moving with a constant velocity drops a ball on the platform. The path of the ban as seen by an observer standing on the platform is – (1) A straight line (2) A circle (3) A parabola (4) None of these

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Last Answer : A parabola

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If a car is traveling at 20 meters per second in a straight line, how many seconds will it take the car to stop if it decelerates at 5 meters per second squared?

Description : If a car is traveling at 20 meters per second in a straight line, how many seconds will it take the car to stop if it decelerates at 5 meters per second squared?

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A toy train moves in a circle of 8 meters radius with a speed of 4 meters per second. What is the magnitude of the acceleration of the train?

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A 50 kilogram ice skater glides across the ice in a straight line at 7 meters per second. If she bends down and scoops up a 20 kilogram child standing on the ice, what will be the final speed of the skater and the child? w) 1 meter per second x) 3 meters per second y) 5 meters per second z) 7 meters per second

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Last Answer : ANSWER: Y -- 5 METERS PER SECOND

An object with a mass of 5 kilograms is a distance of 5 meters above the surface of the earth. If the acceleration due to gravity is 10 meters per second squared, the potential energy of the object relative to the surface of the earth is: w) 10 joules x) 20 joules y) 100 joules z) 250 joules e) none of the above

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A man throws a ball to maximum horizontal distance of 80 meters. Calculate the maximum height reached.

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Two goods trains having equal lengths, take 30 seconds and 45 seconds respectively to cross a telegraph post. If the length of each train is 360 meters, in what time (in seconds) will they cross each other when traveling in opposite direction? A) 36 B) 12 C) 24 D) 48

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The velocity of a ball tossed vertically into the air is expressed by the equation v(t) = -32t + 4, where t is given in seconds. Give the velocity of the ball when it reaches its highest point.

Description : The velocity of a ball tossed vertically into the air is expressed by the equation v(t) = -32t + 4, where t is given in seconds. Give the velocity of the ball when it reaches its highest point. 

Last Answer : ANSWER: 0