Mechanics | Relativity Answers

A large man sits on a four-legged chair with his feet off the floor. The combined mass of the man and chair is 95.0 kg. If the chair legs are circular and have a radius of 0.500 cm at the bottom, what pressure does each leg exert on the floor?

A passenger on a train traveling at 95 km/h north walks towards the back of the train at 2.0 km/h relative to the train. The passenger’s velocity relative to the ground is:

. Determine the angle of the two vectors a and b where their magnitudes are 11 units and 14 units, respectively. Their

resultant vector is 70.04.

On a frictionless horizontal air table, puck A (mass 0.246 kg) is moving to the right toward puck B (mass 0.667 kg), which is initially at rest. Puck A collides inelastically with puck B. After the collision, puck A has velocity 0.207 m/s to the left, and puck B has velocity 0.532 m/s to the right.

1. What was the speed of puck A before the collision?
2. Calculate the initial kinetic energy of puck A.
3. Calculate the change in total kinetic energy of the system that occurs during the collision.

A car accelerates uniformly from 12.5m/s at 10.0 degrees South of West to 105.0 m/s at 85.0 degrees South of West in 7.00 s. Determine the x and y components of the vehicles displacement. Determine the magnitude and direction of the vehicles displacement vector.

A horizontal force of 33.8 N is applied to a 5.8 kg box that slides on a horizontal surface. The box starts from rest moves a horizontal distance of 8.7 meters and obtains a velocity of 5 m/s. The surface has friction. The frictional force in newton is

1.)A 20 – kilogram box of dog food is being pushed by an applied force and accelerates at 2 m/s2. A. Compute for its applied force if a frictional force of 50 N is acting in the opposite direction. B. Construct a free-body diagram to illustrate. 2.)A 2 – kilogram block of wood accelerates at 4 m/s2 along a rough road with a 10N force of friction acting in the opposite direction. a. Compute for the applied force needed. b. Construct a free-body diagram to illustrate. 3.) A van that is 1500 kg is moving with an initial velocity of 25 m/s in a time interval of 1.5 seconds before coming to a stop. Compute for the net force of the moving van. 4.)Gerard played golf with his friends. He hit the ball in a time interval of 0.0500 seconds with an applied force of 500 N. Compute for its impulse.

A ball is thrown horizontally from a building  high with a speed . Find the (a) vertical and horizontal components of the ball’s intial velocity, (b) time of flight, (c) distance from the foot of the building where the ball will strike the ground, and (d) velocity when the ball will strike the ground.