Christmas study

First half Mechanics

Q1.

Define each of the following: displacment, a scalar, acceleration, momentum, weight, pressure, archimedes principle, boyles law, work, power.

Q2.

A man raises a block of mass 100kg to a height of 30m in 10 seconds. Find the average power.

Q3.

A stone is thrown vertically upward with an initial speed of 50m/s, find the greatest height reached?

Q4.

Derive the third equation of motion.

Q5.

A man try’s to open a window who's locking system can withstand a force of 5000Nm. He uses a crowbar of length 0.75m to the fulcrum. He applies a force of 150 newtons. The distance from the fulcrum to the window where the force is felt is 2cm. Will the man manage to break in?

Q6.

Find the value of acceleration due to gravity on a planet who's radius is 2x10⁸m and who's mass is 8x10⁸kg. Use you answer to find the weight of a person of mass 80kg on this planet.

Q7.

Find the gravitational force of attraction between two metal spheres of mass 120kg if the distance between the surface of the spheres is 2m and the radius of each is 0.5m.

Q8.

A cube of side 20cm is placed at a depth of 1.2m in water. Find the pressure at the top and bottom of the block?

Q9.

What is the difference between displacement and distance?

Q10.

A man of mass 80kg mounts a staircase which is 3 m high he does this in 20 seconds. What power is being used by the man?