A - a child sliding down a water slide :)
Let her initial velocity be U.
Let the width of the river be W.
She swims 3/5 the width of the river at U.
Remainder width = (1 - 3/5) = 2/5.
She then swims 2/5 the width with velocity U/2.
Average Speed = (Total Distance Traveled) / ( Total Time Taken).
Distance = Speed * time
time = Distance / Speed.
Time in first trip: = (3/5)W / U = 0.6W/U.
Time in second trip = (2/5)W / (U/2) = 0.4W / 0.5 U = 0.8W/U
Total Distance Traveled = W, width of the river.
Average Speed = W / (0.6W/U + 0.8W/U) = W / (1.4W/U)
= W * U / 1.4W
= U/1.4
= U * 10 / 14
= (5/7) U.
Therefore Average speed is (5/7) of the initial speed.
Answer:
- Here we use the conservation of momentum theorem.
- m stands for mass, and v stands for velocity. The numbers refer to the respective objects.
- m1v1 + m2v2 = m1vf1 + m2vf2
- Since the equation is perfectly inelastic, the final velocity of both masses is the same. Let’s account for this in our formula.
- m1v1 + m2v2 = vf(m1 + m2)
<u>Let’s substitute in our givens.</u>
(0.002 kg)(700 m/s) + (5 kg)(0 m/s) = vf(0.002 kg + 5 kg)
I assume you are proficient in algebra I, so I will not include the steps to simplify this equation.
Note that I have considered the bullet’s velocity to be in the positive direction,
The answer is vf = 0.280 m/s
A tide of increased range that occurs during the new and full moons is called Spring Tide.
