If an object is on a frictionless surface, to keep it at a constant velocity you can’t apply any force because otherwise, the object will accelerate, and the velocity will change.
The old electricity meters with disk using sapphire bearings for friction to be minimal to not aggravate metering
Answer: C. gravitational kinetic
Explanation: Gravitational potential energy is the energy calculated from an object's mass height and the acceleration due to gravity. The gravitational potential energy is the energy an object has as a result of the position of the object in a gravitational field.
Answer:
300 m/s
Explanation:
The difference in time between the two bangs is 1 s.
Thus;
t2 - t1 = 1
We know that distance/time = speed.
Thus;
d2/v - d1/v = 1
Multiply through by v to get;
d2 - d1 = v
Where v is speed of sound in air.
d1 = 350 m
d2 = (150 × 2) + 350 = 650 m
Thus;
v = d2 - d1 = 650 - 350 = 300 m/s