Mechanics | Relativity Answers

A sprinter accelerates from rest to her top velocity at a rate of 3.80m/s2. After reaching her top velocity, she runs the remainder of the race at constant velocity. She completes the 50.00m long race in 7.88s . How far does the sprinter run while she is accelerating ?

A football quarterback throws a pass at an angle of 32.5°. He releases the pass 3.50 m behind the line of scrimmage. His receiver left the line of scrimmage 2.1 s earlier, going straight down-field at a constant speed of 7.50 m/s. With what speed must the quarterback throw the ball so that the pass lands gently in the receiver's hands without the receiver breaking stride? Assume that the ball is released at the same height it is caught and that the receiver is straight downfield from the quarterback at the time of release. (Ignore any effects due to air resistance.)

You are watching your friend play hockey. In the course of the game, he strikes the puck in such a way that, when it is at its highest point, it just clears the surrounding 2.88 m high Plexiglas wall that is 13.1 m away. (Ignore any effects due to air resistance.)
(a) Find the vertical component of its initial velocity.
v0y = ______ m/s

(b) Find the time it takes to reach the wall.
Δt = _______-s

(c) Find the horizontal component of its initial velocity, and its initial speed and angle.
v0x = _______m/s
v0 = _______ m/s
θ = _______°

A tennis ball with a mass of 60 g was moving at a velocity of 3 m/s. How fast would a ball of mass 20g have to be going to have the same momentum as the tennis

a box of mass 50kg is pulled on a incline 12m long and 2m high by the constant force of 100N from rest.it acquires velocity of 2m/s on reaching ,work done against frictional force is ???

A piece of ice of mass 50kg is pushed with a velocity of 5m/s along a horizontal surface.as a result of friction between the piece of ice and the surface,the piece stops after travelling 25m,the ice melted in the process is_____________.

Does change in blood flow between two points constitute a change in velocity (i.e change in position) or acceleration (i.e. change in velocity)? The question stipulates that blood flow slows at a constant rate. Point 1 = 0.30m.s-1 & Point 2 = 0.20 m.s-1.

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if the unbalance force on the ball is 7.25*10^-2n and 4.35*10^-2j of work is done to lift the ball how far does the catcher lift the ball?

A 6 Kg cart on a level surface is pulled at a constant velocity of 2 m/sec by a constant force of 10 N. What is the acceleration? What is the friction force opposing the motion?

A baseball is hit so that it travels straight upward after being struck by the bat. A fan observes that it takes 3.20 s for the ball to reach its maximum height.
(a) Find its initial velocity.
(b) Find the height it reaches.