Explanation:

Question 1.

A light and a heavy object have the same momentum. Find out the ratio of their kinetic energies. Which one has a larger kinetic ENERGY?

Question 2.

An object with 100 N weights is raised to a height of 15m. Find the potential energy possessed by the object at that height. Also find the new potential energy:

a.If the same object is raised half of its original height.

b.If the same object is raised to THREE times of its original height?

Given g=10m/s2

Question 3.

Define one joule of kinetic energy?

Question 4.

A ball of mass 2kg is thrown up with a speed of 10m/s. find the kinetic energy of the ball at the time of throwing. Also find the potential energy of the ball at the highest point?

Question 5.

An object of mass m and velocity v has kinetic energy= 200J. Find the new kinetic energy if the mass of the object BECOMES double and velocity still remains the same?

Question 6.

Calculate the kinetic energy of a car of mass 500kg MOVING with a velocity of 36km/h. Find the kinetic energy if the velocity of car doubles?

Question 7.

Calculate the power of an electric motor that can lift 800 kg of water to store in a tank at a height of 1500cm in 20s. (g=10m/s2).

Question 8.

Calculate the electrical energy consumed in Joules if a toaster of 60 W is used for 30 minutes?

Question 9.

An electric heater of 1000 W is used for two hours in a day? What is the cost of using it for a month of 28 days, if one unit costs 3.00 rupees?

Question 10.

What energy transformation takes place in :

a.Dry cell

b.electric fan

all the best