Answer:

Explanation:
= normal force acting on the coin
Normal force in the upward direction balances the weight of the coin, hence

= frequency of rotation
Angular velocity of turntable is hence given as

= distance from the axis of rotation
= minimum coefficient of static friction
static frictional force is given as

The static frictional force provides the necessary centripetal force , hence
Centripetal force = Static frictional force

Answer:
C) unbalanced
Explanation:
Equal forces acting in opposite directions are called balanced forces. Balanced forces acting on an object will not change the object's motion. When you add equal forces in opposite direction, the net force is zero.
When a car hits you in a rear end collision, the car initially has a momentum going in one direction. This causes your car to move in the same direction that car was moving even if you were at rest. So, for conservation of momentum, you initially have momentum going in the east direction for example, after the collision, you will have a change in momentum which causes you to have a velocity in the west direction. This is because you are initially at rest and then there is a sudden change in velocity so when you speed up, that momentum causes you to move backwards. If you don't have a properly adjusted neckrest you could may experience whiplash.
6. B. 4 electrons
7. Carbon is in everything and it's a compound that all organisms need
8. D. 3
9. Nitrogen gas is almost 80% of the atmosphere
10. Diatomic molecules compose 2 atoms