Answer:
C
Explanation:
why because if something is conserved, it is constant, and does not change with time. A moving body may change its position, acceleration, and velocity with time, but it's energy is constant. The conversation of energy law states that: In any closed system (isolated system) the total energy of the system remain constant.
Mathematically it is written as
Answer:
Acceleration of the car is .
Explanation:
It is given that,
Initial speed of the car, u = 29 m/s
Finally it reaches a speed of, v = 34 m/s
Distance, d = 110 m
We need to find the acceleration of the car as it speed up. It can be calculated using third law of motion as :
So, the acceleration of the car as it speeds up is . Hence, this is the required solution.
Answer:
78.4 KN/m
Explanation:
Given
mass of person 'm' =80 kg
car dips about i.e spring stretched 'x'= 1 cm => 0.01m
acceleration due to gravity 'g'= 9.8 m/s^2
as we know that,in order to find approximate spring constant we use Hooke's Law i.e F=kx
where,
F = the force needed
x= distance the spring is stretched or compressed beyond its natural length
k= constant of proportionality called the spring constant.
F=kx ---> (since f=mg)
mg=kx
k=(mg)/x
k=(80 x 9.8)/ 0.01
k=78.4x
k=78.4 KN/m