Answer:
The average velocity is 180 km/hr
Explanation:
Given;
initial velocity, u = 60 km per hour
final velocity, v = 120 km per hour
initial time = 1 hour
final time = 2 hour
Initial position = 60 km/h x 1 hour = 60 km
final position = 120 km/h x 2 hour = 240 km
The average velocity is given by;
Therefore, the average velocity is 180 km/hr
Answer:
a
This a closed system because the mass of the system is conserved
The energy system that undergoes change is the Potential energy system
The energy system diagram is shown on the first uploaded image
b
Work done = Change in gravitational potential energy
So solving algebraically for work done would be
Work done =
where m is mass
g is acceleration due to gravity
and h is the height
c
Work done in terms of force and distance is = mg
where m is mass of bucket and
g is acceleration due to gravity
Explanation:
a) At the start, potential and kinetic energy were zero. so, energy is zero.
As the person pulls the bucket up, the potential energy becomes mgh.
so,final energy will be consisting of only potential energy.
B) Here work done is equal to change in gravitational potential energy.
W =
W = m*g*h
where g = 9.9 m/
C) Work = force * distance
mgh = force * h
force = mg
force = weight of bucket
