Answer:
The velocity of the skateboard is 0.774 m/s.
Explanation:
Given that,
The spring constant of the spring, k = 3086 N/m
The spring is stretched 18 cm or 0.18 m
Mass of the student, m = 100 kg
Potential energy of the spring, 
To find,
The velocity of the car.
Solution,
It is a case of conservation of energy. The total energy of the system remains conserved. So,
v = 0.774 m/s
So, the velocity of the skateboard is 0.774 m/s.
Answer:
They will not meet
h-hX=1.2*g*t²
hX=v0*t-(1/2*g*t²)
Explanation:
fall h=1/2*g*t²
elevation time if v0=20 m/s te=v0/g=20 m/s /9.81 m/s²=2.0387s
hmax=v0²/(2*g)=(400 m²/s²)/19.62 m/s²2=20.387 m
free fall
t=2.0387s yields hX=1/2*g*t²=20.387 m
h-hX=200m - 20.387 m=179,613 m.
so, the second body has not enough initianoal speed to reach a meeting point
Decelerate
<u>Explanation:</u>
If a charged object is moving against an electric force, the electric force would cause the charged object to decelerate. Rate of deceleration would depend on the amount of the charge the object posses and amount of the opposing electric force.
This could be understood by visualising a hypothetical situation where a charged object is moving against an electric force. Since the object is charged, it would exert a force in its direction of motion which would be opposed by the electric force, thus causing it to decelerate
