The answer is:
C) The electromagnetic and weak interactions
Hope this helps.
The speed of the spring when it is released is 3.5 m/s.
The given parameters:
- <em>Mass of the block, m = 2.5 kg</em>
- <em>Spring constant, k = 56 N/m</em>
- <em>Extension of the spring, x = 0.75 m</em>
The speed of the spring when it is released is calculated by applying the principle of conservation of energy as follows;

Thus, the speed of the spring when it is released is 3.5 m/s.
Learn more about conservation of energy here: brainly.com/question/166559
Answer:
Work done, W = 6153.31 Joules
Explanation:
It is given that,
Weight of piano, W = F = 7382 N
It is pushed 2.16 meters friction less plank
The angle with horizontal, 
When the piano slide up plank at a slow constant rate. The y component of force is taken into consideration. The net force acting on it is given by :

Work done is given by :



W = 6153.31 Joules
So, the work done in sliding the piano up the plank is 6153.31 Joules. Hence, this is the required solution.
Answer:
0.661 m/s²
Explanation:
g = MG / r²
g = (1.31×10²² kg) (6.67×10⁻¹¹ m³/kg/s²) / (1.15×10⁶ m)²
g = 6.61×10⁻¹ m/s²
g = 0.661 m/s²
As an airplane moves through the air, its wings cause changes in the
speed and pressure of the air moving past them. These changes result in
the upward force called lift.
The Bernoulli principle states that an increase in the speed of a fluid
occurs simultaneously with a decrease in the pressure exerted by the
fluid.
A wing is shaped and tilted so the air moving over it moves faster than
the air moving under it. As air speeds up, its pressure goes down. So
the faster-moving air above exerts less pressure on the wing than the
slower-moving air below. The result is an upward push on the wing—lift!