Answer:
a
Explanation:
the kinetic energy decreases which makes the molecules bond together, that makes them not be able to move much
We can do this with the conservation of momentum. The fact it is elastic means no KE is lost so we don't have to worry about the loss due to sound energy etc.
Firstly, let's calculate the momentum of both objects using p=mv:
Object 1:
p = 0.75 x 8.5 = 6.375 kgm/s
Object 2 (we will make this one negative as it is travelling in the opposite direction):
p = 0.65 x -(7.2) = -4.68 kgm/s
Based on this we know that the momentum is going to be in the direction of object one, and will be 6.375-4.68=1.695 kgm/s
Substituting this into p=mv again:
1.695 = (0.75+0.65) x v
Note I assume here the objects stick together, it doesn't specify - it should!
1.695 = 1.4v
v=1.695/1.4 = 1.2 m/s to the right (to 2sf)
The power developed by the student is 756.9 J/s and remains the same if the student takes the same time to climb the stairs when climbing it in two's and three's.
<h3>What is power?</h3>
Power is the rate at work is done.
- Power = work done/time
- work done = mass × acceleration due to gravity × height
Work done = 65.5 × 10 × (18 × 0.165) = 1945.35 J
Power = 1945.35/2.57 = 756.9 J/s
If the student climbed the steps in two or three at a time, the power does not change if the time remains the same.
- Time required = Energy/ power
The time required to convert the Big Mac meal from McDonalds = 4 853 440/756.9
Time required = 6412.26 seconds
Therefore, from the power developed by the student, it will take him 6412.26 seconds to convert all the energy in a Big Mac meal.
Learn more about power at: brainly.com/question/1634438
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A 300-kg bear grasping a vertical tree slides down at constant velocity. The friction force between the
tree and the bear is
Answer:
correct option is E
power lens is - 1.667 D
Explanation:
Given data
infinity = 60 cm
to find out
power lens
solution
we know here infinity v = -60 cm because object at infinity
and we take u = - infinity
so we know that
1/f = 1/v - 1/u
1/f = 1 / -60 - 1 / -infinity
so
1/f = - 1/60
f = - 60 cm = 0.60 m
and we know power of lens = 1/f
so here
power = 1 / -0.60
power = - 1.667 D
so correct option is E
power lens is - 1.667 D
