The freezing point ..... :)
mass of the bottle in each case is M = 0.250 kg
now as per given speeds we can use the formula of kinetic energy to find it
1) when speed is 2 m/s
kinetic energy is given as


2) when speed is 3 m/s
kinetic energy is given as


3) when speed is 4 m/s
kinetic energy is given as


4) when speed is 5 m/s
kinetic energy is given as


5) when speed is 6 m/s
kinetic energy is given as


Answer:
296 N
Explanation:
Draw a free body diagram. The box has two forces on it: tension up and weight down.
Apply Newton's second law:
∑F = ma
T − mg = ma
T = m (g + a)
Given m = 196 N / 9.8 m/s² = 20 kg, and a = +5 m/s²:
T = (20 kg) (9.8 m/s² + 5 m/s²)
T = 296 N
Answer:

Explanation:
Regardless of the initial velocity of the pebble, the acceleration of the pebble is equal to the gravitational acceleration which is equal to 9.8 m/s2 towards downwards direction.
This can be shown by Newton's Second Law. According to the law, the net force applied on an object is equal to mass times acceleration of that object.
During the downward motion, the only force acting on the pebble is the gravitational force, hence its acceleration is equal to gravitational acceleration.