Unbalanced because if it is pushing then stopping, that means that it is unbalanced.
Answer:
80 m/s
Explanation:
Given:
a = -5 m/s²
v = 0 m/s
Δx = 640 m
Find: v₀
v² = v₀² + 2a(x − x₀)
(0 m/s)² = v₀² + 2(-5 m/s²) (640 m)
v₀ = 80 m/s
To calculate the initial velocity of the bike, we use the following equation
.
or

Here, u is initial velocity, v is final velocity, t is the time and d is the distance covered by bike.
Given,
,
and
.
Substituting these values in above equation, we get
.
Thus, the initial velocity of the bike is 1.2 m/s.
We can solve the problem by using the first law of thermodynamics, which states that:

where

is the change in internal energy of the system
Q is the heat absorbed by the system
W is the work done by the system
In our problem, the heat absorbed by the system is Q=+194 kJ, while the work done is W=-120 kJ, where the negative sign means the work is done by the surroundings on the system. Therefore, the variation of internal energy is
The answer is centimeters.