A. Coal is used to primarily to produce and generate electricity and it is responsible for 39 percent of the power supply for the united states.
You will need to turn this into scientific notation, so:
1.176 × 10^1 cm^2
To two significant figures means to two digits so since 7 is greater than 5, you will need to round up.
Final answer is:
1.2×10^1 cm^2
I assume the 100 N force is a pulling force directed up the incline.
The net forces on the block acting parallel and perpendicular to the incline are
∑ F[para] = 100 N - F[friction] = 0
∑ F[perp] = F[normal] - mg cos(30°) = 0
The friction in this case is the maximum static friction - the block is held at rest by static friction, and a minimum 100 N force is required to get the block to start sliding up the incline.
Then
F[friction] = 100 N
F[normal] = mg cos(30°) = (10 kg) (9.8 m/s²) cos(30°) ≈ 84.9 N
If µ is the coefficient of static friction, then
F[friction] = µ F[normal]
⇒ µ = (100 N) / (84.9 N) ≈ 1.2
Answer:
because the dog cat moster ate a bean. the answer is 68
Explanation: