chapter number 7 Flashcards
Force , Work and Energy
what do you apply when you pull or push a thing?
force is applied when we pull or push a thing.
Is it true to state that a thing always moves on applying force?
No, it is not true to state that a thing always moves on applying force
What is the force generated by your body?
The force generated by our body is muscular force.
What generates magnetic force?
Magnet generates magnetic force.
Is friction a force?
Yes, friction is a force.
What kind of a machine is a hammer?
Hammer is a simple machine.
What make a sailboat move?
Wind energy and the flowing water makes a sailboat move.
How is force of friction generated?
Force of friction is generated when two separate surfaces rub against each other.
What type of energy does a washing machine use?
Washing machine uses electrical energy.
Name the form of energy that a rolling rock or a moving truck possesses.
The form of energy that a rolling rock or a moving truck possesses is called mechanical energy
A bicycle is a complex machine. justify the statement.
A bicycle is a complex machine because it is made up of different kind of parts like paddle, brake, tire, handle, seat etc.
what happens when force is applied on a moving ball?
When force is applied on a moving ball, it can make it move faster, it can slow down, it can stop or it can change the direction of motion of the ball.
Write a few lines about the gravitational force of the Earth.
Few line about the gravitational force of the Earth are the force that pulls everything towards the Earth is called gravitational force of the Earth or gravity of the Earth. Fruits from a tree, always fall to the ground. This is because the Earth pulls everything towards itself.
What are the types of forces
The types of forces are:-
1) Muscular force. example The bicycle moves when we use our legs, turn by turn and apply force on the pedal.
2) Gravitational force of the Earth. example when we throw a ball up in the air it always falls back on the ground.
3) Magnetic force. example A magnet pull the iron object towards itself.
4) Frictional force. example a bicycle has hand brakes on both wheels. When the brakes are applied, they rub against the wheels. Friction between the brakes and the wheels slow down and stops the bicycle.
Which force is essential for an object to move? Explain with examples.
Muscular force is essential for an object to move for example during a game of tug-of-war, we use muscular force.
