Answer:
a) 


b) 

c)

Explanation:
We have:
m: is the ball's mass = 1.5 kg
v₀: is the initial speed = 15 m/s
g: is the gravity acceleration = 9.81 m/s²
a) In the initial position we have:
h: is the height = 0
The potential energy is given by:

The kinetic energy is:

And the mechanical energies:

b) At 5 m above the initial position we have:
h = 5 m
The potential energy is:

Now, to find the kinetic energy we need to calculate the speed at 5 m:



And the mechanical energies:
c) At its maximum height:
: is the final speed = 0

Now, the potential, kinetic and mechanical energies are:

I hope it helps you!
Answer:
When you climb, earth exerts gravitational force on pack in downward direction(pointing towards the center of earth).
In order to climb, you need to work against work done by gravity on the pack.
Hence work done by you = work done by gravity on pack
= Force x displacement = 70 x 30 = 2100 J.
So you need to do 2100 joules of work to lift your pack.
Power is the rate of work done.
Therefore power = work done by you/time(in seconds)
= 2100/600 =3.5 watts
Explanation:
Answer:
When it is marked with its cubic-inch volume
Explanation:
Because this allows for best and efficient identification
Answer:

Explanation:
From the question we are told that
Nucleus diameter 
a 12C nucleus
Required kinetic energy 
Generally initial speed of proton must be determined,applying the law of conservation of energy we have

where
=initial kinetic energy
=final kinetic energy
=initial electric potential
=final electric potential
mathematically

where
=distance b/w charges
=nucleus charge 
=constant
=proton charge
Generally kinetic energy is know as

Therefore
Generally equation for radius is 
Mathematically solving for radius of nucleus


Generally we can easily solving mathematically substitute into v_1









Therefore the proton must be fired out with a speed of 
Answer:
1, 2 and 3
Explanation:
The most dense substance will settle at the bottom of the cup