Answer:
If it is not an object in motion, all forces are balanced.
We do not feel the gravitational forces from objects other than the Earth because they are weak.
Answer:
A
B

C

D

Explanation:
Considering the first question
From the question we are told that
The spring constant is 
The potential energy is 
Generally the potential energy stored in spring is mathematically represented as 
=>
=>
=>
Considering the second question
From the question we are told that
The mass of the dart is m = 0.050 kg
Generally from the law of energy conservation

=> 
=> 
Considering the third question
The height at which the dart was fired horizontally is 
Generally from the law of energy conservation

Here KE is kinetic energy of the dart which is mathematical represented as

=> 
=> 
=> 
Considering the fourth question
Generally the total time of flight of the dart is mathematically represented as

=> 
=> 
Generally the horizontal distance from the equilibrium position to the ground is mathematically represented as

=> 
=> 
Answer:
6.21 m/s
Explanation:
Using work energy equation then

where d is displacement from initial to final position, v is velocity and subscripts a and b are position A and B respectively, m is mass of collar, g is acceleration due to gravity
Substituting 1 Kg for m, 0.4m for h,
as 0, 9.81 for g then

<h2>
Answer: 745.59 nm</h2>
Explanation:
The diffraction angles
when we have a slit divided into
parts are obtained by the following equation:
(1)
Where:
is the width of the slit
is the wavelength of the light
is an integer different from zero
Now, the first-order diffraction angle is given when
, hence equation (1) becomes:
(2)
We know:
In addition we are told the diffraction grating has 750 slits per mm, this means:
Solving (2) with the known values we will find
:
(3)
(4)
Knowing
:
>>>This is the wavelength of the light, wich corresponds to red.