Gravitational potential energy=mass*gravitational acceleration*heightKinetic energy = 0.5*mass*velocity²Thus:K.E0.5*1*x²=12.5x²=12.5/(0.5*1)x=√12.5/(0.5*1)x=5
GPEmass*gravitational acceleration*height1*9.81*h=98h=98/(9.81*1)h= 9.98 J approximately, rounded 10meters
Answer:
Explanation:
This figure given is the frequency; 2 times per second represents frequency.
What is frequency?
- It is the number of times per seconds something goes past or around another.
it is expressed as:
Frequency = 
where n is the number of turns
t is the time taken
Therefore, the Barber spinned him 2 times in 1 second.
The period is the inverse of frequency. It is the time taken for a body to go through a point;
Period =
=
s
False, wood is a solid structure that is not see through
Consider the upward direction of motion as positive and downward direction of motion as negative.
a = acceleration due to gravity in downward direction = - 9.8 
v₀ = initial velocity of rock in upward direction = ?
v = final velocity of rock at the highest point = 0 
t = time to reach the maximum height = 4.2 sec
Using the kinematics equation
v = v₀ + a t
inserting the values
0 = v₀ + (- 9.8) (4.2)
v₀ = 41.2 