Of the cliff?
Projectile motion
In the problem we are asked to find a height of certain cliff when a motorcycle stunt driver zoom out horizontally at the end the cliff at an initial velocity. So we will use one of the kinematics equation for projectile motion,
y
=
v
o
y
t
+
1
2
g
t
where
v
o
y
is just equal to zero since we can assume that the driver zooms out horizontally,
g
=
9.8
m
/
s
2
and
t
is time after
Answer:
80%
Explanation:
Efficiency = Power output / Power input × 100 %
To calculate efficiency we need to find power output of electric pump.
We can use,
Work done = Energy change
Work done per second = Energy change per second
Work done per second = Power
Therefore, Power = Energy change per second
= Change in potential energy of water per second
=mgh / t
= 200× 10×6 / 10
= 1200 W = 1.2 kW
Now use the first equation to find efficiency,
Efficiency =
× 100%
= 80 %
Answer:
Change/ Potential
Explanation:
Work is the amount of energy required to perform an action that is for a force to cause a displacement.
From work-energy theorem, work done by body is equal to change in its kinetic energy.
Work of gravity is basically the potential energy stored in the body due to gravity. From the law of conservation of mechanical energy, increased kinetic energy comes from the change of the potential energy of the stone.
Answer:
32cm³
Explanation:
Given parameters:
Density of substance = 2.7g/cm³
Mass of substance = 86.4g
Unknown:
Volume of substance = ?
Solution:
Density is the mass per unit volume of a substance.
Density = 
Since the unknown is volume we solve for it;
mass = density x volume
86.4 = 2.7 x volume
volume =
= 32cm³