Mechanics | Relativity Answers

A monkey in a perch 20 m high in a tree drops a coconut above the head of a zoo keeper as he runs with a speed 1.5
m/s beneath the tree actually intending to hit the toes of the zoo keeper. How early in seconds should the coconut be dropped by the monkey?

A block of mass 2 kg is connected to a freely hanging block of mass 4 kg by a light and inextensible string which
passes over pulley at the edge of a table. The 2 kg mass is on the surface of the table assumed to be smooth. Calculate
the acceleration of the system and the tension in the string

A 20 kg block on an inclined plane is pulled up the plane with rope tied to the block. The rope is at angle of 37 degrees
above the surface of the plane. The tension in the rope is 250 N and the frictional force on the block is 8.0 N.What is the
acceleration of the block?

A 15 kg block rests on the surface of a plane inclined at an of 30 degrees to the horizontal. A light inextensible string
passing over a small, smooth pulley at the top of the plane connects the block to another 13 kg block hanging freely. The
coefficient of kinetic friction between the 15 kg block and the plane is 0.25. Find the acceleration of the blocks

A 2 kg and a 4 kg hang freely at opposite ends of a light inextensible string which passes over a small and light pulley
fixed to a rigid support. Calculate the acceleration of the system

Which of the following quantities has the same dimensions as work?
momentum
impulse
moment of a force
g = 9:8m=s2
pressure

Which of the following is not true?
A crate sliding across the floor does work against frictional forces
Work is done if a component a force acting on an object exists in the direction of its displacement
A man with a bag of cement on his head does work to move the bag of cement as he walks from place to place on a
flat horizontal floor
Work is a scalar quantity

Which of the following properties of a ball is conserved as it falls freely in a vacuum?
kinetic energy
gravitational potential energy
monentum
mechanical energy

How much work is done when a bucket of mass 1.5 kg with 10 kg of water in it is pulled up from the bottom of a well 8
m deep? Take g = 9:8m/s2

A 65 kg sprinter completes a 100 m race in 9.83 s. Calculate the average kinetic energy of the sprinter