The (more) speed an object has, the (lower) the potential energy and the (higher) the kinetic energy. (I believe that is correct but it’s been a while since I’ve done this)
Momentum = mass x velocity so if velocity is kept same and mass is increased then momentum will increase.
Answer:
3.8 secs
Explanation:
Parameters given:
Acceleration due to gravity, g = 9.8 
Initial velocity, u = 11.76 m/s
Final velocity, v = 49 m/s
Using one of Newton's equations of linear motion, we have that:

where t = time of flight of arrow
The sign is positive because the arrow is moving downward, in the same direction as gravitational force.
Therefore:

The arrow was in flight for 3.8 secs
Answer:
Magnetism is the force exerted by magnets when they attract or repel each other.