Answer: I feel that 3 is the answer
Explanation: Let there be 2 objects, A and B
A is at height of 5m whereas B is at height of 15m
so over here let the gravitational potential energy of A be x
and since B is 3 times higher than A B=3x
Since, earth is considered to be the point where gravitational potenial is 0
So hence forth and object 3 times up will have 3 times the gravitational potential energy of A
Answer:
C) 16.3 ml
Explanation:
Density is equal to the ratio between the mass of an object and its volume:

where
m is the mass
V is the volume
In our problem, we know:
- density of aluminium: 
- mass of the aluminium foil: 
So we can re-arrange the equation above and use these data to find the volume of the piece of aluminium foil:

Answer:
23. 4375 m
Explanation:
There are two parts of the rocket's motion
1 ) accelerating (assume it goes upto h1 height )
using motion equations upwards

Lets find the velocity after 2.5 seconds (V1)
V = U +at
V1 = 0 +5*2.5 = 12.5 m/s
2) motion under gravity (assume it goes upto h2 height )
now there no acceleration from the rocket. it is now subjected to the gravity
using motion equations upwards (assuming g= 10m/s² downwards)
V²= U² +2as
0 = 12.5²+2*(-10)*h2
h2 = 7.8125 m
maximum height = h1 + h2
= 15.625 + 7.8125
= 23. 4375 m