Answer:
Weight and Mass !!!!!!
Explanation:
Galileo discovered that objects that are more dense, or have more mass, fall at a faster rate than less dense objects, due to this air resistance. A feather and brick dropped together. Air resistance causes the feather to fall more slowly.
Answer:
![\Delta K=0.07969 J - 0.0849 J = -0.00521 J](https://tex.z-dn.net/?f=%5CDelta%20K%3D0.07969%20J%20-%200.0849%20J%20%3D%20-0.00521%20J)
Explanation:
According to the law of conservation of linear momentum, the total momentum of both pucks won't be changed regardless of their interaction if no external forces are acting on the system.
Being
and
the masses of pucks a and b respectively, the initial momentum of the system is
![M_1=m_av_a+m_bv_b](https://tex.z-dn.net/?f=M_1%3Dm_av_a%2Bm_bv_b)
Since b is initially at rest
![M_1=m_av_a](https://tex.z-dn.net/?f=M_1%3Dm_av_a)
After the collision and being
and
the respective velocities, the total momentum is
![M_2=m_av'_a+m_bv'_b](https://tex.z-dn.net/?f=M_2%3Dm_av%27_a%2Bm_bv%27_b)
Both momentums are equal, thus
Solving for ![v_a](https://tex.z-dn.net/?f=v_a)
![v_a=\frac{m_av'_a+m_bv'_b}{m_a}](https://tex.z-dn.net/?f=v_a%3D%5Cfrac%7Bm_av%27_a%2Bm_bv%27_b%7D%7Bm_a%7D)
![v_a=\frac{0.254Kg\times (-0.123 m/s)+0.367Kg (0.651m/s)}{0.254Kg}](https://tex.z-dn.net/?f=v_a%3D%5Cfrac%7B0.254Kg%5Ctimes%20%28-0.123%20m%2Fs%29%2B0.367Kg%20%280.651m%2Fs%29%7D%7B0.254Kg%7D)
The initial kinetic energy can be found as (provided puck b is at rest)
![K_1=\frac{1}{2}m_av_a^2](https://tex.z-dn.net/?f=K_1%3D%5Cfrac%7B1%7D%7B2%7Dm_av_a%5E2)
![K_1=\frac{1}{2}(0.254Kg) (0.8176m/s)^2=0.0849 J](https://tex.z-dn.net/?f=K_1%3D%5Cfrac%7B1%7D%7B2%7D%280.254Kg%29%20%280.8176m%2Fs%29%5E2%3D0.0849%20J)
The final kinetic energy is
![K_2=\frac{1}{2}m_av_a'^2+\frac{1}{2}m_bv_b'^2](https://tex.z-dn.net/?f=K_2%3D%5Cfrac%7B1%7D%7B2%7Dm_av_a%27%5E2%2B%5Cfrac%7B1%7D%7B2%7Dm_bv_b%27%5E2)
![K_2=\frac{1}{2}0.254Kg (-0.123m/s)^2+\frac{1}{2}0.367Kg (0.651m/s)^2=0.07969 J](https://tex.z-dn.net/?f=K_2%3D%5Cfrac%7B1%7D%7B2%7D0.254Kg%20%28-0.123m%2Fs%29%5E2%2B%5Cfrac%7B1%7D%7B2%7D0.367Kg%20%280.651m%2Fs%29%5E2%3D0.07969%20J)
The change of kinetic energy is
![\Delta K=0.07969 J - 0.0849 J = -0.00521 J](https://tex.z-dn.net/?f=%5CDelta%20K%3D0.07969%20J%20-%200.0849%20J%20%3D%20-0.00521%20J)
Answer:
A. Speed
Explanation:
Speed is the magnitude of velocity, which is given in the question. Velocity is a vector quantity and therefore has both a magnitude and a direction. Only the former is implied in the question.
An object in motion will stay in motion unless acted upon another force.
Newton used this to prove that gravity existed. Without an unseen force, we could throw a ball and it would go on forever correct? Unless there was something to pull it down, in this case, gravity.