Answer:
V
I and II
III and IV
Explanation:
The impulse is equal to the change in momentum of the object involved, so we can calculate the change in momentum in each situation and compare them all.
Taking always east as positive direction, and labelling
u the initial velocity
v the final velocity
m = 1000 kg the mass (which is always equal)
We find:
(i)
u = 25 m/s
v = 0

(II)
u = 25 m/s
v = 0

(III)
In this case,
F = 2000 N is the force
is the time
So the magnitude of the impulse is

(IV)
F = 2000 N is the force
is the time
So the magnitude of the impulse is

(V)
u = 25 m/s
v = -25 m/s

So the ranking from largest to smallest is:
V
I and II
III and IV
Answer:
28.6260196842 m
Explanation:
Let h be the height of the building
t = Time taken by the watermelon to fall to the ground
Time taken to hear the sound is 2.5 seconds
Time taken by the sound to travel the height of the cliff = 2.5-t
Speed of sound in air = 340 m/s
For the watermelon falling

For the sound
Distance = Speed × Time

Here, distance traveled by the stone and sound is equal


The time taken to fall down is 2.4158 seconds

Height of the buidling is 28.6260196842 m
Answer: 1. decreasing the mass of both objects
2. decreasing the mass of one of the objects
3. increasing the distance between the objects
Explanation: Hope that helped! (:
Answer:
71nC is the total charge of the rod
Explanation:
See attached file
Answer:
Resistivity of both wires are same
Explanation:
Length of one wire,
Diameter,
Radius,




Temperature in each case is same.
Area of each wire,
Resistivity is the property of material due to which it offers resistance to the flow of current.
Resistivity of material depends upon the temperature and material by which it is made.
It does not depends upon the length of object.
Therefore, the resistivity of both wires of different length are same.