A ball drops some distance and gains 30 J of kinetic energy. How much gravitational potential energy did the ball start with? Do
1 answer:
Answer:
The gravitational potential energy of the ball is more than 30 J.
Explanation:
Given that,
Gains kinetic energy = 30 J
We need to calculate the gravitational potential energy
According to law of conservation of energy
If there is no air resistance then the potential energy of the ball fully converted into kinetic energy.
If the air resistance is considered then the potential energy used to do work against air resistance.
According to question,
A ball drops some distance and gains 30 J of kinetic energy and considers air resistance then 30 J of potential energy can be loosed by the ball.
Hence, The gravitational potential energy of the ball is more than 30 J.
You might be interested in
Answer:
The total time it is in the air for the ball is 1.6326 s
Given:
Initial velocity = 8
To find:
the total time it is in the air = ?
Formula used:
t =
Where t = time to reach maximum height
v = final velocity of the ball = 0 m/s
u = initial velocity of ball = 8 m/s
a = acceleration due to gravity = -9.8
Acceleration of gravity is taken as negative because ball is moving in opposite direction.
Solution:
A ball is thrown upward at time t=0 from the ground with an initial velocity of 8 m/s.
The time taken by the ball to reach the maximum height is given by,
t =
Where t = time to reach maximum height
v = final velocity of the ball = 0 m/s
u = initial velocity of ball = 8 m/s
a = acceleration due to gravity = -9.8
Acceleration of gravity is taken as negative because ball is moving in opposite direction.
t =
t = 0.8163 s
Thus, time taken by the ball to reach the ground again = time taken to reach maximum height
So, Total time required for ball to reach ground = 2t = 2 × 0.8163
Total time required for ball to reach ground = 1.6326 s
The total time it is in the air for the ball is 1.6326 s
Given:
initial angular speed, = 21.5 rad/s
final angular speed, = 28.0 rad/s
time, t = 3.50 s
Solution:
Angular acceleration can be defined as the time rate of change of angular velocity and is given by:
Now, putting the given values in the above formula:
Therefore, angular acceleration is: