Answer:
Stars are powered by nuclear fusion in their cores, mostly converting hydrogen into helium. The production of new elements via nuclear reactions is called nucleosynthesis. A star's mass determines what other type of nucleosynthesis occurs in its core (or during explosive changes in its life cycle).
The law applied here is Newton's first law, also known as, law of inertia.
This law states that: A body will retain its state of rest or motion unless acted upon by an external force.
If you are moving and the bus suddenly stops, your body will lurch forward trying to retain its state of motion until it comes to rest and changes its state by the external force acted on it.
If you are at rest and the bus suddenly moves, your body will lurch backwards trying to retain its state of rest and opposing the force of motion until it is forced to change its state by this force.
The scale would need 10 aluminum cubes on one side. Figure out how many paper clips would be needed on the other side to balance this. You have to use more than one aluminum cube because you need to have enough cubes so that you get a whole number mass. 10 cubes gives you a total mass of 27 g for the aluminum.
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We use the equation of motion for vertical component,
Here, 
is displacement of bullet, 
is vertical initial velocity of bullet which is equal to zero because bullet was fired horizontally, and t is time of flight.
Therefore,
Given, 
Substituting the values, we get time of flight
