Question

Can anyone explains all the answers?

1. Two balls, A and B are thrown at the same angle above horizontal, but initial velocity of ball A is two times greater than initial velocity of ball B. Ignore air resistance. we can conclude that horizontal range covered by ball A is

1. same as range covered by ball B
2. twice the range covered by ball B
3. four times the range covered by ball B.
4. greater than horizontal range covered by ball b, but we don’t know how exactly greater.

2. An airplane moving with speed 200 m/s dropped a box of supplies. Ignore the air resistance acting of a box.  What is position of a box at the moment when it hits the ground?

1. In front of airplane
2. Under the airplane
3. Behind the airplane
4. We can’t say without knowing mass of the box.

3. Three balls are kicked from the ground level at some angles above horizontal with different initial speeds. All three balls reached in their paths the samemaximum height. Ball A covered the total horizontal range D; ball B covered the total  horizontal range 1.5D and ball C covered total horizontal range 2D when they hit the ground.  Which of these balls has the greatest horizontal component of velocity?

1. A
2. B
3. C
4. They all have the horizontal component of velocity

4. Ball A is thrown vertically up with initial velocity 20 m/s. Ball B is thrown at 60⁰ below vertical direction with initial velocity 40 m/s.  Ignore air resistance. Pick a right statement about time it takes for these balls to come back to initial height:

1. It will take a greater time for ball A to return to initial height.
2. It will take greater time for ball B to return to initial height.
3. The time it will take to return to the same height is the same for both balls.
4. This time will depend on mass and radius of balls.

5. Consider two vectors, A of magnitude 3 units and B of magnitude of 4 units. You add these two vectors to each other and resulting vector C has the magnitude 6 units. We can conclude than:

1. A and B are directed in the same direction.
2. A and B are perpendicular to each other.
3. A and B are directed  in opposite directions.
4. A and B are directed at some angle to each other. This angle is bigger than 90 but less than 180.
5. A and B are directed at some angle to each other. This angle is bigger than 0 but less than 90.

Answer 1