If this is a true or false question, it is True.
Answer:
When the ball hits the ground, its velocity is -128 ft/s.
Explanation:
Hi there!
First, let's find the time it takes the ball to reach the ground (the value of t for which s(t) = 0):
s(t) = -16t² + 32t + 240
0 = -16t² + 32t + 240
Solving the quadratic equation with the quadratic formula:
t = 5.0 s (the other solution of the equation is rejected because it is negative).
Now, we have to find the velocity of the ball at t = 5.0 s.
The velocity of the ball is the change of height over time (the derivative of s(t)):
v = ds/dt = s'(t) = -32t + 32
at t = 5.0 s:
s'(5.0) = -32(5.0) + 32 = -128 ft/s
When the ball hits the ground, its velocity is -128 ft/s.
Answer:
A. The brakes used a coil system to convert the kinetic energy into potential energy stored in the brakes
Explanation:
Based on the law of conservation of energy, the brakes used a coil system to convert the kinetic energy into potential energy stored in the brakes.
The law of conservation of energy states that energy is neither created nor destroyed in a system but it is transformed from one form to another.
As the airplane slows down, the kinetic energy which is presented in the motion of the plane is gradually converted to potential energy.
The potential energy is the energy due to the position of a body.
To throw an object into the space you need to throw it with the escape velocity of the earth which is 11.2 km/sec. therefore if you can throw an object with the speed of 11.2 km/sec it will leave the earth atmosphere and will reach to the space.
Answer: 13062.5 N
What average force is required to stop an 1100-kg car in 8.0 s if it is traveling at 95 km/h? i got the answer to be 13062.
