Answer:
B, to predict star count
Explanation:
the rest can be done with rulers, Einstein cans and public surveys, we can't predict how many stars there will be, but we can take pictures of them instead
Answer:
W = 600 J
Explanation:
We have,
According to attached figure,
Height of the inclined plane is 60 m
Force acting on the block is 10 N
It is required to find the work must be done against gravity to move it to the top of the incline. The work done is given by :
W = mgh
or

So, the work done against the gravity is 600 J.
Answer:
151.9 N
Explanation:
Force = mass x acceleration
Acceleration due to gravity is 9.8 m/s^2 (you should memorize this number).
F = ma
F = (15.5)(9.8)
F = 151.9
So we want to know what is the purpose of a lanyard attached to a safety switch. So in case the operator falls overboard a safety switch is installed and connected to the operators hand or waist. Which ever is more practical. This safety switch turns off the motor.
Answer:
you need to multiply the momentum and the mass