Answer: 17.68 s
Explanation:
This problem is a good example of Vertical motion, where the main equation for this situation is:
(1)
Where:
is the height of the ball when it hits the ground
is the initial height of the ball
is the initial velocity of the ball
is the time when the ball strikes the ground
is the acceleration due to gravity
Having this clear, let's find
from (1):
(2)
Rewritting (2):
(3)
This is a quadratic equation (also called equation of the second degree) of the form
, which can be solved with the following formula:
(4)
Where:



Substituting the known values:
(5)
Solving (5) we find the positive result is:

Answer:
Explanation:
The cannonball goes a horizontal distance of 275 m . It travels a vertical distance of 100 m
Time taken to cover vertical distance = t ,
Initial velocity u = 0
distance s = 100 m
acceleration a = 9.8 m /s²
s = ut + 1/2 g t²
100 = .5 x 9.8 x t²
t = 4.51 s
During this time it travels horizontally also uniformly so
horizontal velocity Vx = horizontal displacement / time
= 275 / 4.51 = 60.97 m /s
Vertical velocity Vy
Vy = u + gt
= 0 + 9.8 x 4.51
= 44.2 m /s
Resultant velocity
V = √ ( 44.2² + 60.97² )
= √ ( 1953.64 + 3717.34 )
= 75.3 m /s
Angle with horizontal Ф
TanФ = Vy / Vx
= 44.2 / 60.97
= .725
Ф = 36⁰ .
Given: The mass of stone (m) = 0.5 kg
Raised from heights (h₁) = 1.0 m to (h₂) = 2.0 m
Acceleration due to gravity (g) = 9.8 m/s²
To find: The change in potential energy of the stone
Formula: The potential energy (P) = mgh
where, all alphabets are in their usual meanings.
Now, we shall calculate the change in potential energy of the stone
Δ P = P₂ - P₁ = mg (h₂ - h₁)
or, = 0.5 kg ×9.8 m/s² ×(2.0 m - 1.0 m)
or, = 4.9 J
Hence, the required change in the potential energy of the stone will be 4.9 J
Explanation:
Given that,
Wavelength of the light, 
(a) Slit width, 
The angle that locates the first dark fringe is given by :



(b) Slit width, 
The angle that locates the first dark fringe is given by :



Hence, this is the required solution.