Question

iv: Which of the following is an example of friction that is helpful?
@) Brakes used on a bike
b) Tires from a car on the road
c) Tread on the bottom of your shoes
d) All are examples that are helpful
v: How can friction be reduced?
@reduce the force acting between the 2 surfaces
b) reduce the roughness of the 2 surfaces coming in contact
c) use wax, grease or oil
d) all of the above are ways of reducing friction
vi: Which would NOT be a way of reducing friction?
a) making the surfaces smoother
6) using lubricants such as waxes, oils, or grease
c) changing from sliding friction to rolling friction using ball bearings
d) Using kitty litter on snow and ice to help your car gain traction
vii: What are 2 factors that determine the amount of friction between 2 objects?
a) Force and roughness between surfaces
b) hills and valleys and how smooth or rough the surface is
c) Amount of force and amount of surface the comes in contact
d) The force and the weight exerted on the surfaces
viii: Examples of friction in my everyday life.
a) When I am going on a run and have to stop quickly before crossing a street, I can stop
because of the friction between my shoes and the sidewalk
6) When I am riding my bike and have to stop at a stop sign, it slows because of the friction
between the breaks and the wheels
c) When I mow the lawn, the engine has a lot of moving parts, and they rub on each other
d) There is friction in my joints​

Answer 1

Answer:

iv) option a

v) option d

vi)option d

Answer 2

The questions are answered below:

iv: The following is an example of friction that is helpful- d) All are examples that are helpful.

Brakes stop the vehicles preventing accidents. Tires can only traverse because of friction. We can only tread because of friction between shoes and the surface.

v. Friction can be reduced by d) all of the above are ways of reducing friction.

Reducing roughness reduces friction. using wax, grease, or oil can lubricate the surface reducing friction. Force reduction will also reduce friction.

vi. This NOT be a way of reducing friction - Using kitty litter on snow and ice to help your car gain traction

Using kitty litter will increase roughness and thus friction.

viii: Examples of friction in my everyday life.

- When I am going on a run and have to stop quickly before crossing a street, I can stop because of the friction between my shoes and the sidewalk

Friction between shoes and the sidewalk is necessary to stop the motion quickly.

- When I am riding my bike and have to stop at a stop sign, it slows because of the friction

As brakes are applied, the vehicle stops due to friction.

- When I mow the lawn, the engine has a lot of moving parts, and they rub on each other

While mowing the parts will experience friction as they will rub against each other.

- There is friction in my joints​

Joints can have static as well as kinetic friction.