Answer:

Explanation:
If the object is rolling without slipping, every unit of rotated angle equals to a distance perimeter rotated.
Suppose the object complete 1 revolution within time t. The angular distance is 2π rad. Its angular velocity is 2π/t
The distance it covered is its circumference, which is 2πr, and so the speed is 2πr/t
So the linear speed compared to angular speed is


Place the boxes 10cm apart, if they are closer that concentrates the mass of the boxes more
A.. in case of any problems that may occur you would know what company to call
Answer:
v = 0.99 c = 2.99 x 10⁸ m/s
Explanation:
From the special theory of relativity:

where,
v = speed of travel = ?
c = speed of light = 3 x 10⁸ m/s
t = time measured on earth = 90 years
t₀ = time measured in moving frame = 6 months = 0.5 year
Therefore,

<u>v = 0.99 c = 2.99 x 10⁸ m/s</u>
Answer:
Explanation:
Let acceleration of fall be a .
v² = u² + 2as
v = 3.8 m /s
u = 0
s = 3.5 m
3.8² = 0 + 2 x a x 3.5
a = 2.06 m /s²
Since this acceleration is less than g , an upward force is acting on the firefighter in the form of friction . Let this force be F . Let mass of the firefighter be m .
m = 765 / 9.8
= 78.06 kg
mg - F = ma
765 - F = 78.06 x 2.06
765 - F = 160.8
F = 604.2 N .