Explanation:
Assuming we can turn on the lightbulb from any distance with a device. We can gradually increase the distance that separates us from lightbulb, in this way, if the speed of light is finite we can see a temporary delay between the moment we turn on the lightbulb and the moment in which we observe its light.
Answer: v = 0.6 m/s
Explanation: <u>Momentum</u> <u>Conservation</u> <u>Principle</u> states that for a collision between two objects in an isolated system, the total momentum of the objects before the collision is equal to the total momentum of the objects after the collision.
Momentum is calculated as Q = m.v
For the piñata problem:
Before the collision, the piñata is not moving, so 
.
After the collision, the stick stops, so 
.
Rearraging, we have:
Substituting:
0.6
Immediately after being cracked by the stick, the piñata has a swing speed of 0.6 m/s.
F = kq1q2/r^2
<span>q1 is first charge </span>
<span>q2 is second charge </span>
<span>k is 9 E9 </span>
<span>r is distance between them </span>
<span>F = (9E9)(2 E-6)(4 E-6)/2^2 = 0.018 N </span>
<span>A postive answer indicates a repulsive force</span>
Its very simple if a body is moving in circle the magnitude of its velocity remain constant but its direction changes because velocity is directed towards tangent and at every point in a cirlce its direction will be different (along tangent) so velocity is not uniform .As acceleration is the rate change of velocity so it will be non zero because velocity is changing due to its direction.
