Answer:
d = 105 m
Explanation:
Speed of a car, v = 21 m/s
We need to find the distance traveled by the dar during those 5 s before it stops. Let the distance is d. It can be calculated as :
d = v × t
d = 21 m/s × 5 s
d = 105 m
So, it will cover 105 m before it stops.
NB: The diagram of the pulley system is not shown but the information provided is sufficient to answer the question
Answer:
Power = 2702.56 W
Explanation:
Let the power consumed be P
Energy expended = E = mgh
height, h = 5 m
E = 80 * 9.8 * 5
E = 3920 J

To calculate the time, t
From F = ma
F = 900 N
900 = 80 a
a = 900/80
a = 11.25 m/s²
From the equation of motion, 
The drill head starts from rest, u = 0 m/s

Power, P = E/t
P = 3920/0.0.943
P = 4157.79 W
But Efficiency, E = 0.65
P = 0.65 * 4157.79
Power = 2702.56 W
Conductor because it creates heat.
if the color changes, it is neutral but if it stays the same, it is an acid.