Answer:
Velocity is a change in displacement over change in time and uses the units m/s.
Both are rates of change and can be positive or negative.
Acceleration is a change in velocity over change in time and uses the units m/s².
Explanation:
Velocity is the change in displacement over change in time, this makes it a rate of change. It can be positive or negative because it is a vector quantity. It uses the units m/s because that is a displacement unit over a time unit.
Acceleration is the change in velocity over change in time, this makes it a rate of change. It can be positive or negative because it is also a vector quantity. It uses the units m/s² (m/s/s) because that is a velocity unit over a time unit.
Answer:
Around 2.8212 sec
Explanation:
Given the eqn x=1/2at^2+vot
your vo=0
39=1/2(-9.8)t^2
=7.95=t^2
=2.82sec
Answer:
20 m/s
Explanation:
The speed of a wave is given by:

where
is the wavelength
f is the frequency
v is the speed
For the wave in this problem,
f = 10 Hz is the frequency
is the wavelength
So the speed is

Answer:
The kinetic energy of the merry-go-round is
.
Explanation:
Given:
Weight of the merry-go-round, 
Radius of the merry-go-round, 
the force on the merry-go-round, 
Acceleration due to gravity, 
Time given, 
Mass of the merry-go-round is given by

Moment of inertial of the merry-go-round is given by

Torque on the merry-go-round is given by

The angular acceleration is given by

The angular velocity is given by

The kinetic energy of the merry-go-round is given by

Answer:
Her error was that she did not subtract 12 from 8 correctly
Explanation:
Jackie did 8-12 instead of 12-8