Answer:
28.5 m/s
Explanation:
There are 2 different velocities: the train velocity and yours velocity. They're in opposite directions, so one is positive and other is negative. Take the forward direction as the positive:
V = +30 -1.5
V = 28.5 m/s
Answer:
The speed of the bob when it passes the lowest point 
Explanation:
Given data

When a pendulum swinging back & forth then at highest point the velocity is zero and lowest point velocity is maximum.
Velocity at lowest point is given by



Therefore the speed of the bob when it passes the lowest point 
Use the formula for kinetic energy.
KE=1/2mv^2
KE=1/2*(82kg)*(2.8m/s)^2
KE=321.4 J
The answer is C
Liquid is not a solid object so make sure you define them
The answer is B because that that will make it more powerful but less lasting.