Answer:+1.25 m/s
Explanation:
Given
mass of ice skater M=70 kg
mass of ball m=10 kg
the initial velocity of the ball 
Conserving linear momentum
![M\times0+m\timesu_1=(M+m)v\quad \quad [v=\text{combined velocity of skater and ball}]](https://tex.z-dn.net/?f=M%5Ctimes0%2Bm%5Ctimesu_1%3D%28M%2Bm%29v%5Cquad%20%5Cquad%20%5Bv%3D%5Ctext%7Bcombined%20velocity%20of%20skater%20and%20ball%7D%5D)

Therefore the velocity of the person holding the ball is 1.25 m/s
This collision represents the perfectly inelastic collision where particles stick together after the collision.
The answer is B, because all energy is released at once in static electricity.
There’s a quizlet that mentions these questions, if you are having trouble. I’d suggest to give them a look.
The greatest amount of kinetic energy is found with the train because it takes most energy to reach that velocity and also to slow down to a halt.
Answer:
Explanation:
Given:
P = 6.35 atm
= 1.01 × 10^5 × 6.35
= 6.434 × 10^5 N/m^2
As = 975 cm^2
D = 3.8 g/cm^2
M = 320 kg
Since the propellant volume is equal to the cross sectional area, As times the fuel length, the volumetric propellant consumption rate is the cross section area times the linear burn rate, bs , and the instantaneous mass flow rate of combustion, ms gases generated is equal to the volumetric rate times the fuel density, D
ms = D × As × bs
ms ÷ bs = M/L
M/L = 3.8 × 975
= 3705 g/cm
= 3.705 × 10^6 kg/m^3
Pressure = mass × g/area
= mass/length × time^2
t = sqrt(3.705 × 10^6/6.43 × 10^5)
= 2.4 s
The answer is B. momentum