Class 8 Science CH-12 Friction

Friction is a

• Non-contact force

• Contact force

• Magnetic force

• Electrostatic force

Which of the following produces least friction?

• Sliding friction

• Rolling friction

• Composite friction

• Static friction

Friction always

• Opposes the motion

• Helps the motion

• Both (a) and (b)

• None of these

Friction can be reduced by using

• Oil

• Grease

• Powder

• All of these

Static friction is less than

• Sliding friction

• Rolling friction

• Both (a) and (b)

• None of these

Whenever the surfaces in contact tend to move or move with respect to each other, the force of friction comes into play

• Only if the objects are solid.

• Only if one of the two objects is liquid.

• Only if one of the two objects is gaseous.

• Irrespective of whether the objects are solid, liquid or gaseous.

To sharpen the blade of a knife by rubbing it against a surface, which of the following will be most suitable?

• Stone

• Plastic block

• Wooden block

• Glass block

The shape of an Aeroplane is like a

• Dog

• Bird

• Car

• All of these

Friction is

• Foe

• Friend

• Both (a) and (b)

• None of these

Tags

NGSS.MS-PS2-2

Friction due to fluids is called

• Force

• Pressure

• Friction

• Drag