Answer:
Potential energy of the object will be equal to mgh
Explanation:
Let the mass of the object is m
Acceleration due to gravity is 
Let the object is released from height h
We have to find the potential energy
Potential energy is of an object released from height h is equal to
, here m is mass, g is acceleration due to gravity and h is height from which object is released.
Explanation:
Trains that use magnetic levitation (maglev) are suspended above the track, which greatly reduces friction from the rails and allows the trains to travel between 250 and 300 miles per hour! Magnetic levitation uses attractive and repulsive magnetic forces to suspend and control the speeds and motion of the trains.
Answer: 37.5 km
Explanation:
The question is that
If you ran 15 km/hr for 2.5 hours, how much distance would you cover ?
Where
Speed = 15 km/ hr
Time = 2.5 hours
Using the formula for speed.
Speed = distance/time
Substitute speed and time into the formula
15 = distance/ 2.5
Make distance the subject of formula by cross multiplying.
Distance = 15 × 2.5
Distance = 37.5 km.
Let's call this "certain amount" with a variable, x, (since it's not specified in the question, I will assume that the answer shall just be based on this variable).
So every additional floor will make the building sink by x, and let's make the unit cm, so x cm.
Now we know that the maximum depression is 20 cm, and it is also
x*y, where y is the number of floors.
So we have x*y=20,
therefore the number of floors is:
20/x or This is the answer