Answer:
The speed of the mouse relative to the factory floor is 5 m/s.
Explanation:
Given that,
A factory conveyor belt rolls at 3 m/s, 
A mouse sees a piece of cheese directly across the belt and heads straight for the cheese at 4 m/s, 
To find,
The mouse's speed relative to the factory floor.
Solution,
The resultant velocity of the mouse is given by the resultant of two velocities. It is given by :
v = 5 m/s
So, the speed of the mouse relative to the factory floor is 5 m/s.
I think it is known as a pulsar!
Matter<span> doesn't </span><span>disappear </span>
BIg, big questions in Thermodynamics. ...
Not without "help" it can't. There are two versions of this. One is that it is impossible to take heat from something and convert it completely into work - there has to be some waste at a lower temperature. The other is that heat will not "spontaneously" go from a colder place to a warmer place. So, a domestic fridge needs a device to transfer the heat, that's that buzzing sound of a motor driving a refrigerant round in a cycle, taking heat out the fridge and making the surrounding warmer. It's also called a heat pump. The area near where the pump puts its heat can be felt to be warm.
