Question

A student rolls a marble on two different surfaces with the same force. He observed that the marble travelled a greater distance on a glossy paper but not on the sand paper. Why?
1 point
Interlocking between the surface of marble and sand paper is high
Interlocking between the the surface of marble and glossy paper is high
Mass of marble on sand paper is high
Mass of marble on glossy paper is high​

Answer 1

Answer:

Rough surfaces have more microscopic hills and valleys than smooth surfaces do. So, the rougher the surface is, the greater the friction is. ... The amount of kinetic friction between two surfaces depends in part on how the surfaces move. Surfaces can slide past each other, or a surface can roll over another surface.

Answer 2

Answer:

Explanation:

impulse=FΔt=mΔv

                so we have to find the velocity with which ball strikes the ground : v

1

​

=

2gh

​

=

2×10×20

​

=20

s

m

​

and for finding speed with which it rebounds such that it goes to a height of 5m will be                  

                                 v

2

​

=

2gh

​

=

2×10×5

​

=10

s

m

​

so, impulse=m(v

2

​

−v

1

​

)=0.10×(20−10)=1N−s

                     F=

dt

dP

​

=1/0.01=100N