Explanation:
W = PE
W = mgh
1500 J = (20 kg) (9.8 m/s²) h
h = 7.65 m
Round as needed.
Answer:
A)s = 104.16 m
b)s= 104.16 m
Explanation:
Given that
u = 25 m/s
μ = 0.3
The friction force will act opposite to the direction of motion.
Fr= μ m g
Fr= - m a
a=acceleration
μ m g = - m a
a= - μ g
a= - 0.3 x 10 m/s² ( take g= 10 m/s²)
a= - 3 m/s²
The final speed of the mass is zero ,v= 0
We know that
v² = u² +2 a s
s=distance
0² = 25² - 2 x 3 x s
625 = 6 s
s = 104.16 m
By using energy conservation
Work done by all the forces =Change in the kinetic energy

Negative sign because force act opposite to the displacement.



- 3 x 2 x s = - 625
s= 104.16 m
Answer:
C. Burning coal tends to harm the environment more than using solar panels.
Explanation:
When coal is burned, it reacts with the oxygen in the air. This reaction converts the stored potential energy, which turns into thermal energy, which is released as heat. But it also produces methane and carbon dioxide which is released into the air.
Answer:
Explanation:19,2 or 0/4 or 5 or 40,4
Time = (distance) / (speed)
Time = (150 x 10⁹ m) / (3 x 10⁸ m/s) =
50 x 10¹ sec =
<em>500 sec</em> = 8 min 20 sec