Answer:
+5.7 m/s
Explanation:
According to the law of conservation of momentum is that the momentum before the collision is equal to the momentum after the collision. In an equation form it would look like this:
M₁V₁+M₂V₂ = M₁V₁'+M₂V₂'
Where:
M₁ = mass of object 1 (kg)
V₁ = velocity of object 1 before the collision (m/s)
V₁' = Final velocity of object 1 after the collision (m/s)
M₂ = mass of object 2 (kg)
V₂ = velocity of object 2 before the collision (m/s)
V₂' = Final velocity of object 2 after the collision (m/s)
According to your problem you have the following given:
M₁ = 5 g = 0.005kg
V₁ = 3 m/s
V₁' = -5m/s (It bounced off so it is going the other direction)
M₂ = 6g = 0.006kg
V₂ = -1 m/s (It is coming from the opposite direction of the 3-ball)
V₂' = ?
So we plug in what we know and solve for what we don't know.

Answer:
0.0003
Explanation:
In the rules of Sig Figs, all zeros before with decimals are not sigificant. I.E. 0.00000000000000009. Despite how many 0's there are, only the 9 is significant. Zeros before a number is not significant. In 100, only the one is signficant in 100. with a dot at the end, the one and the two zeros are significant. hope this helps.
Answer:
The length of the rod should be

Explanation:
Period of simple pendulum is given by

We have

The length of the rod should be

Answer:
(v2 - v1) / t = a for uniform acceleration
a = (10.5 - 15) / 4 = -1.125 m / s^2
T = 15 / 1.125 = 13.3 s time for train to stop from 15 m/s
S = V0 T + 1/2 a T^2
S = 15 * 13.3 - 1.125 / 2 * 13.3^2
S = 199.5 - 99.5 = 100 m