Answer:
Explanation:
Given
Volume of paint is 
Area of cover 
Suppose paint to be a rectangular box with thickness t and volume V
therefore we can write as




Explanation:
For each object, the initial potential energy is converted to rotational energy and translational energy:
PE = RE + KE
mgh = ½ Iω² + ½ mv²
For the marble (a solid sphere), I = ⅖ mr².
For the basketball (a hollow sphere), I = ⅔ mr².
For the manhole cover (a solid cylinder), I = ½ mr².
For the wedding ring (a hollow cylinder), I = mr².
If we say k is the coefficient in each case:
mgh = ½ (kmr²) ω² + ½ mv²
For rolling without slipping, ωr = v:
mgh = ½ kmv² + ½ mv²
gh = ½ kv² + ½ v²
2gh = (k + 1) v²
v² = 2gh / (k + 1)
The smaller the value of k, the higher the velocity. Therefore:
marble > manhole cover > basketball > wedding ring
The answer is b i just did the test
Answer:
The velocity of the arrow after 3 seconds is 30.02 m/s.
Explanation:
It is given that,
An arrow is shot upward on the moon with velocity of 35 m/s, its height after t seconds is given by the equation:

We know that the rate of change of displacement is equal to the velocity of an object.

Velocity of the arrow after 3 seconds will be :

So, the velocity of the arrow after 3 seconds is 30.02 m/s. Hence, this is the required solution.
Answer:
W = 19.845 J
Explanation:
Work is defined as W = Fdcos
, where F is the force exerted and d is the distance. Because the direction the ball is falling is the same direction as the force itself,
= 0 deg, and since cos(0) = 1, this equation is equivalent to W = Fd. In this case, the force exerted is the weight force, which is equivalent to m * g. Substituting you get:
W = mgd = 0.810 kg * 9.8 m/s^2 * 2.5m
W = 19.845 J