Answer:
efficiancy=40 percent
Explanation:
efficiency=energy output/energy input×100
efficiancy=8J/20J×100
efficiancy=0.4×100
efficiancy=40 percent
Mark brianliest if my answer suit your question..
B) 20-40 percent
I hope this helps
Answer:
This is an open circuit
Explanation:
An open circuit I believe
It needs to be closed for the bulb to be turned on
Answer:
16.935 N
Explanation:
In order to make the box start moving, the level force applied on the box (F) must be greater than the force of static friction that keeps the box at rest, which is equal to

where
is the coefficient of static friction
(mg) = 30 N is the weight of the box
Therefore, the condition for F must be:

So, the applied force must be greater than this value.
Answer:

Explanation:
The angular acceleration is:


And the angular deceleration is:


The total number of revolutions is:


