Answer:
Explanation:
A ) The surface is frictionless . If the box is at rest , there will be no tension in the rope.
B ) In this case , the box is moving with steady rate of 4.20 m /s . In this case also no force is acting on the box so tension in the rope will be nil.
C ) In this case the box is moving with acceleration of 5.8 m /s² so force on the box = mass x acceleration
= 57 x 5.8
= 330.6 N .
So tension in the rope will be equal to force acting on the rope . Hence tension = 330.6 N .
Answer:
bueno lo siguiente es que yo no sé inglés
Answer:

Explanation:
Use the equation:
(where T is the period)
(9 comes from the period of a full wavelength)

Explanation:
by the formula, v²-u²=2aS
S=12m, a=2m/s², v=25m/s, u=?
v²-u²=2aS
25²-u²=2×2×12
-u²=48-625
-u²=-577
u²=577
u=√577
u = 24.02m/s
hope this helps you.
The classical physics works on the Newton's laws of motion. It is applicable on heavenly bodies which are governed by the gravitational force. On the other hand, Quantum Physics is applicable for very low mass and sized bodies like electron, protons etc. The classical physics would accurately describe the motion of satellite moving with speed 7500 m/s using the following formula:

where G is the gravitational constant, M is the mass of the planet and v is the orbital speed. Then radius of the orbit can be described by this formula.