Answer:
Stratosphere and Thermosphere
Explanation: Both of these layers above earth heat as you go higher.
Answer:
Coefficient of friction is 
.
Work done is 
.
Explanation:
Given:
Mass of the box (
): 
kg
Force needed (
): 
N
The formula to calculate the coefficient of friction between the floor and the box is given by
Here, 
is the coefficient of friction and 
is the acceleration due to gravity.
Substitute N for , kg for and 
m/s² for into equation (1) and solve to calculate the value of the coefficient of friction.
The formula to calculate the work done in overcoming the friction is given by
Here, 
is the work done and 
is the distance travelled.
Substitute N for and 
for into equation (2) to calculate the work done.
Answer: 780080
Explanation: BY FORMULA OF K.E
K.E= 1/2 MV^2
= 1/2 (1990)(28)^2
= 780080 JOULE
The potential energy of a 25 kg bicycle resting at the top of a hill 3 m high will be 735.75 J.
<h3>What is potential energy?</h3>
The potential energy is due to the virtue of the position and the height. The unit for the potential energy is the joule.
The potential energy is mainly depending upon the height of the object. when the cyclist is at the highest position, the height is maximum. Therefore, the potential energy is also maximum.
The potential energy is found as;
PE=mgh
PE=25 kg× 9.81 m/s² ×3 m
PE= 735.75 J.
Hence, the potential energy of a 25 kg bicycle resting at the top of a hill 3 m high will be 735.75 J.
To learn more about the potential energy, refer to the link;
brainly.com/question/24284560
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