Answer:
Explanation:
For elestic collision
v₁ = 
![v_2 = [tex]\frac{(m_2-m_1)u_2}{m_1+m_2} +\frac{2m_1u_1}{m_1+m_2}](https://tex.z-dn.net/?f=v_2%20%3D%20%5Btex%5D%5Cfrac%7B%28m_2-m_1%29u_2%7D%7Bm_1%2Bm_2%7D%20%2B%5Cfrac%7B2m_1u_1%7D%7Bm_1%2Bm_2%7D)
[/tex]
Here u₁ = 0 , u₂ = 22 m/s , m₁ = 77 kg , m₂ = .15 kg , v₁ and v₂ are velocity of goalie and puck after the collision.
v₁ = 0 + ( 2 x .15 x22 )/ 77.15
= .085 m / s
Velocity of goalie will be .085 m/s in the direction of original velocity of ball before collision.
v₂ = (.15 - 77)x 22 / 77.15 +0
= - 21.91 m /s
=Velocity of puck will be - 21.91 m /s in the direction opposite to original velocity of ball before collision.
Easy. All you need to do us to is to shorten the number so that it only contains 3 digits. Change 2.9979248 to 2.99. Don't forget to round the number to the last possible digit. In this case, 2.997 would round to 3.00
So the answer would be 3.00x10^8.
Why?
Well, every non-0 number to the left of the decimal point will count as a significant figure. And every number to the right of the decimal point, whether it's 0 or not, will also count as a significant figure.
The 3 to the left of the decimal point and the 2 0s to the right will add up to 3 significant figures.
Answer:
Power = Work / Time
P = m g h / t = 80 kg * 9.8 m/s^2 * 15 m / 39 s = 320 N m/ s = 392 J / s
= 392 Watts
Answer:
option D
Explanation:
given,
mass of the freight car (m) = 5,000 Kg
initial speed of car (u)= 2 m/s
mass of the freight car (M)= 10,000 Kg
initial speed (u')= 0 m/s
speed after collision (V)= ?
using conservation of momentum
m u + M u' = (M + m) V
5000 x 2 + 10000 x 0 = (5000 + 10000) V
couples move away with the speed of
Hence, the correct answer is option D
The weight must have a magnitude equal to the upthrust.
This is by the law of flotation.
