An object with more mass has more kinetic energy than an object with less mass, if both objects are moving at the same speed. <em>(c)</em>
Answer:
the rate that the energy of a system is transformed
Explanation:
We can define energy as the capacity or ability to do work. Power is defined as the rate of doing work or the rate at which energy is transformed. It can also be regarded as the time rate of energy transfer. In older physics literature, power is sometimes referred to as activity.
Power is given by energy/time. Its unit is watt which is defined as joule per second. Another popular unit of power is horsepower. 1 horsepower = 746 watts.
Very large magnitude of power is measured in killowats and megawatts.
Answer: 2.04 s
Explanation:
Let the initial velocity be v, Angle of projectile be
Then the horizontal component = v cos θ = 16 m/s
Vertical component of velocity = v sin θ = 20 m/s
Time taken to reach the highest point is half the time taken for total flight.
Time for total flight,
![t = \frac{2vsin \theta}{g}](https://tex.z-dn.net/?f=t%20%3D%20%5Cfrac%7B2vsin%20%5Ctheta%7D%7Bg%7D)
![t'=\frac{vsin \theta}{g} = \frac {20 m/s}{9.8 m/s^2} = 2.04 s](https://tex.z-dn.net/?f=%20t%27%3D%5Cfrac%7Bvsin%20%5Ctheta%7D%7Bg%7D%20%3D%20%5Cfrac%20%7B20%20m%2Fs%7D%7B9.8%20m%2Fs%5E2%7D%20%3D%202.04%20s)
Thus, the football takes 2.04 s to rise to the highest point of its trajectory.
Density =mass/Volume
0.8=mass/60
Mass=0.8*60
Mass=48g