Explanation:
Given parameters:
Initial velocity = 72km/hr
Final velocity = 0km/hr
Time taken = 25s
Unknown:
Acceleration = ?
Solution:
To solve this problem, convert km/hr to m/s;
1000m = 1km
3600s = 1hr
72km/hr;
1km/hr = 0.278m/s
72km/hr = 0.278 x 72 = 20.02m/s
Acceleration is the change in velocity divided by the time taken;
Acceleration =
Acceleration =
= -0.8m/s
The car is actually decelerating at a rate of 0.8m/s
Answer:
v=115 m/s
or
v=414 km/h
Explanation:
Given data

To find
Terminal velocity (in meters per second and kilometers per hour)
Solution
At terminal speed the weight equal the drag force

For speed in km/h(kilometers per hour)
To convert m/s to km/h you need to multiply the speed value by 3.6
If the length and linear density are constant, the frequency is directly proportional to the square root of the tension.
Potential energy decreases and kinetic energy increases.
Potential energy is related to the height, since the wagon is going downhill, height decreases and potential energy decreases.
Kinetic energy is related to the speed, since the wagon is speeding up, kinetic energy increases.
Answer: find the answer in the explanation as kinetic energy converts to potential energy.
Explanation:
Before the truck driver sees a dog running into the road, The mechanical energy state of the truck will be kinetic energy at maximum.
Immediately he applied the brakes, the mechanical energy of the truck will be combination of kinetic energy and potential energy.
The kinetic energy will gradually decrease as potential energy continue to increase till it reaches maximum potential energy.
The truck will come to a stop at maximum potential energy