NCERT 5th Class (CBSE) Science: Force and Energy – Simple Machine

Question: What is force?

Answer: A push or pull acting on an object is called force.

Question: What is gravity?

Answer: The force that attracts objects towards the center of the earth is called gravity.

Question: What is magnetism?

Answer: The push or pull applied by a magnet on metals like iron and nickel and on other magnets is called magnetism.

Question: What is energy? Name any four types of energy.

Answer: The ability to do work is called energy. The four types of energy are heat energy, light energy, wind energy and sound energy.

Question: What is a machine?

Answer: A machine is a tool that makes our work easier by helping us overcome a larger force (load) by applying lesser force (effort).

Question: Name the six types of simple machines.

Answer: The six types of simple machines are:

1. Lever
2. Pulley
3. Wheel and axle
4. Wedge
5. Screw
6. Inclined plane

Question: List the four effects that force have on objects.

Answer: The four effects that force have on objects are:

1. A force can make a stationary object move or make a moving object move faster.
2. A force can make a moving object stop or slow down.
3. a force can change the direction in which an object is moving.
4. A force can change the shape of an object.

Question: What is friction? Why is friction necessary?

Answer: The force that tries to stop the sliding movement of objects across a surface is called friction. Friction is necessary because friction between or feet and ground makes it possible for us to walk.