Answer:
The direction of the contact forces acting on a body is not necessarily perpendicular to the contact surface. The resolution of contact forces in two components i.e. perpendicular to contact surface and along surface. Perpendicular component is normal force and parallel component is friction.
Explanation:
<span>Glass is transparent meaning light passes through it and therefore you can see through it, but some light reflects back and if the surface is very smooth as glass often is then the light reflected back can be seen as a reflected image.</span>
That's called the wave's "wavelength" .
Answer:
20m/s
Explanation:
it covers 20 metres in a second