Answer:
Mass = 18.0 kg
Explanation:
From Hooke's law,
F = ke
where: F is the force, k is the spring constant and e is the extension.
But, F = mg
So that,
mg = ke
On the Earth, let the gravitational force be 10 m/
.
3.0 x 10 = k x 5.0
30 = 5k
⇒ k = 
................ 1
On the Moon, the gravitational force is 
of that on the Earth.
m x 
= k x 5.0
= 5k
⇒ k = 
............. 2
Equating 1 and 2, we have;
=
m = 
= 18.0
m = 18.0 kg
The mass required to produce the same extension on the Moon is 18 kg.
Answer:
Velocity of throwing = 34.335 m/s
Explanation:
Time taken by the tennis ball to reach maximum height, t = 0.5 x 7 = 3.5 seconds.
Let the initial velocity be u, we have acceleration due to gravity, a = -9.81 m/s² and final velocity = 0 m/s
Equation of motion result we have v = u + at
Substituting
0 = u - 9.81 x 3.5
u = 34.335 m/s
Velocity of throwing = 34.335 m/s
Answer:
3.036×10⁻¹⁰ N
Explanation:
From newton's law of universal gravitation,
F = Gm1m2/r² .............................. Equation 1
Where F = Gravitational force between the balls, m1 = mass of the first ball, m2 = mass of the second ball, r = distance between their centers.
G = gravitational constant
Given: m1 = 7.9 kg, m2 = 6.1 kg, r = 2.0 m, G = 6.67×10⁻¹¹ Nm²/C²
Substituting into equation 1
F = 6.67×10⁻¹¹×7.9×6.1/2²
F = 321.427×10⁻¹¹/4
F = 30.36×10⁻¹¹
F = 3.036×10⁻¹⁰ N
Hence the force between the balls = 3.036×10⁻¹⁰ N
Explanation:
It is known that relation between pressure and density is as follows.
P = 
where, P = pressure
= density
g = acceleration due to gravity
h = height
Putting the given values into the above formula as follows.
P =
= 
= 110495000 Pa
Now, relation between pressure and force is as follows.
P = 
or, F = PA
F = 
= 
Thus, we can conclude that a force of can be experienced at such depth.
