Answer:
III. A baseball is traveling at 38 m/s when it hits a wall and bounces away from the wall at -38 m/s
Explanation:
The change in momentum of the baseball is a function of its change in velocity. And can be shown mathematically as;
∆p = m (∆v)
Where ∆p change in momentum
m mass of baseball
∆v change in velocity
Which implies that the higher the change in velocity of the baseball the higher the change in momentum.
I) ∆v = 38 - 0 = 38m/s
II) ∆v = 0 - 38 = -38m/s
III) ∆v = -38-38 = -76m/s
Therefore the third event have the highest change in velocity and thus have the highest change in momentum.
Answer:
D. Left
Explanation:
The question is worded weirdly, but based on the fact that heat transfers from hot to cold and the temperature on the right is warmer than the temperature on the left, I would say that the heat is flowing from the box on the right to the box on the left.
I hope this makes sense and was helpful! ☺
Answer:
It would be 2,500
Explanation:
The KE is 7,500 so the PE would be 2,500
Weight of object = mass x acceleration due to gravity
= 2.5 x 9.8
= 24.5N
Hence option B is correct.
Hope this helps!!
Answer:
3.At equilibrium, its instantaneous velocity is at maximum
Explanation:
The motion of a mass on the end of a spring is a simple harmonic motion. In a simple harmonic motion, the total mechanical energy of the system is constant, and it is sum of the elastic potential energy (U) and the kinetic energy of the mass (K):
where
k is the spring constant
x is the displacement of the spring from equilibrium
m is the mass
v is the speed
As we see from the formula, since the total energy E is constant, when the displacement (x) increases, the speed (v) increases, and viceversa. Therefore, when the mass is at its equilibrium position (which corresponds to x=0), the velocity of the mass will be maximum.
