Answer:
A
Explanation:
Hooke's law! F(spring)=-kx
There's no tricky square law here. The spring constant doesn't change, only x (distance stretched) changes. Therefore, if distance is halved, Force will be halved.
Yes, C is correct. It self explains itself as we know light travels through a vacuum ( doesn't need a medium) and light is a type of electromagnetic wave.
5m/s
100m
Explanation:
Average speed is sum of distance distance traveled in a given time by a body.
Average speed= 
Distance = 20m
time = 4s
Average speed =
= 5m/s
For the spaceship;
Distance covered = speed x time
Speed = 50m/s
time = 2s
Distance covered = 50 x 2 = 100m
learn more:
Average speed brainly.com/question/5063905
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