True! The mechanical advantage of the wheel and axle is equal to the ratio of the radius of the wheel over the radius of the axle.
2.72 N
Explanation:
Step 1:
From the basic formula in electrostatics
F = E * q
where F = Force due to charges
E = Electric field strength
q = Charge
Step 2:
From the given question
q= 
E = 
F =
N
Answer:
Explanation:
From the given information:
The initial PE
= m×g×h
= 5 kg × 9.81 m/s² × 10 m
= 490.5 J
The change in Potential energy P.E of the box is:
ΔP.E = 
ΔP.E = 0 -
ΔP.E = 
If we take a look at conservation of total energy for determining the change in the internal energy of the box;


this can be re-written as:

Here, K.E = 0
Also, 70% goes into raising the internal energy for the box;
Thus,


ΔU = 343.35 J
Thus, the magnitude of the increase is = 343.35 J
Answer: 1666J
Explanation:
Given that,
Mass of box (m) = 10kg
Total distance covered by box (h)
= (5m + 12m)
= 17m
work done on the box = ?
Work is done when force is applied on an object over a distance. Hence, the magnitude of work done on the box depends on its mass (m), distance covered (h), and acceleration due to gravity (g)
(g has a value of 9.8m/s²
i.e Work = mgh
Work = 10kg x 9.8m/s² x 17m
Work = 1666J
Thus, 1666 joules of work was done by the woman on the box.
Answer:
Coring is a defect in an alloy (e.g., a copper nickel alloy) that occurs when a heated alloy is cooled too fast for diffusion to occur.
Explanation: