What is contact force ?

• a force that works when two objects move away from each other

• a force that works when two objects come in contact with each other

• a force that slow down or stop the object from moving

• a force that opposes the motion of an object

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

What happens when you push your pencil box on your desk?

• the box will move to a certain distance and stop

• the box will come back to the original position

• the box will fall down from the table

• the box will not move from its place

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Define friction force.

• is a contact force exerted by a surface as an object moves across it or makes an effort to move across it.

• the force exerted by the muscles

• the force that pulls everything towards the centre of the earth

• the force with which a magnet attracts certain metals.

Tags

NGSS.MS-PS2-2

Which one is a property of frictional force?

• it opposes the motion of an object

• it is less on a rough surface than on a smooth surface

• it is not a contact force

• it tends to increase the speed of the moving object

Why does a ball rolling on the ground comes to rest after sometime?

• the force of friction slows down or stops a moving object

• gravitational force stops the object from moving

• magnetic force slows down or stops a moving object

• muscular force stops the object from moving

Tags

NGSS.MS-PS2-2

THE FRICTION FORCE IS A CONTACT FORCE.

• TRUE

• FALSE

FRICTION TENDS TO ________THE MOVING OBJECT.

___________IS APPLIED ON A CARROM BOARD TO REDUCE FRICTION.

• OIL

• GREASE

• CREAM

• POWDER

USES OF FRICTION?

• WE CAN EAT

• WE CAN THINK

• WE CAN WRITE

WE CAN WRITE BEACUSE OF __________BETWEEN OUR AND PAPER.