Friction is a force. A resistance force that tries to slow down and stop objects in motion. The difference between friction and air resistance is that friction acts on surfaces. For example, if I were skateboarding on a rough surface, more friction would occur so I would travel slower. If I were skareboarding on ice, I would go faster because there is much less friction to slow me down. Hope that helps:)
Answer:
Final speed of the bullet is 228.3 m/s
Explanation:
As we know that there is no external force on the system of wooden block and the bullet
so we can say momentum of the system is conserved here
so here we can say



so we will have


F~1/r²
doubling the distance r, Decreases the force by ¼
Answer : The temperature of the hot reservoir (in Kelvins) is 1128.18 K
Explanation :
Efficiency of carnot heat engine : It is the ratio of work done by the system to the system to the amount of heat transferred to the system at the higher temperature.
Formula used for efficiency of the heat engine.

where,
= efficiency = 0.780
= Temperature of hot reservoir = ?
= Temperature of cold reservoir = 
Now put all the given values in the above expression, we get:



Therefore, the temperature of the hot reservoir (in Kelvins) is 1128.18 K
Answer:
light waves can be converted to electricity through <em>a solar cell</em>
Explanation: