Cool Problems

02/19/2018

An object is free falling from height H and keeps rebounding to about 10% less of its previous height (due to deformations). Find how long it will take until it comes to a rest.

01/19/2018

An object is free falling from height H. During the last second it covers a distance of 3/4 H. Find H

01/13/2018

A full-size drone requires about 200 W to hover (i.e. stay at a constant altitude with no motion along any axis). If we want to built a toy drone that is 50 times smaller from the exact same material, what would be the required power for it to hover? [Hint: this problem can be solved with implementation of UNITS]

12/23/2018

Think how many times you have heard the term "INERTIA"

Now try to think of someone who actually explained to you what "INERTIA" really is. e.g. can you quantify INERTIA. You walk in a store. Can you ask a person "can I please have XXX of whatever units of INERTIA".

In essence INERTIA of an object is its MASS. This is further related to Newton's law of motion. Yes, you read correctly; Newton has ONE law i.e. ΣF=m·a. The "other laws" are direct consequences of this...

12/30/2018

A bus moves between two stations that are 400 m apart. Its acceleration is 2.5 m s-2, its constant speed is 10 m s-1 and deacceleration is 1 m s-2. How long does it take to cover this distance?(solution on the left)

12/30/2018

A bird is flying horizontally at a height h. A fox jumps with speed v2 and an angle θ. If it barely misses catching the bird how can what we tell COLOR is the fox?

01/03/2019

An ice cube is sliding down an inclined plane with friction. If the entire system remains at 0°C how LONG of a plane will it take until the cube melts?

01/03/2019

Many state that: the International Space Station does not have actual gravity but something that is called microgravity. Do you really understand what this means???