Answer:
3600 kg
Explanation:
From the question,
Density = Mass/Volume
D = M/V.............................. Equation 1
Where D = Density of the substance, M = mass of the substance, V = Volume of the subtance.
Make M the subject of the equation
M = D×V ............................ Equation 2
Given: D = 1200 kg/m³, V = 3 m³.
Substitute these values into equation 2
M = 1200×3
M = 3600 kg.
Hence the mass of the substance is 3600 kg
Answer:
c) The wavelength decreases but the frequency remains the same.
Explanation:
Light travels at different speed in different mediums.
Refractive index is equal to velocity of the light 'c' in empty space divided by the velocity 'v' in the substance.
Or ,
n = c/v.
<u>The frequency of the light does not change but the wavelength of the light changes with change in the speed.</u>
c = frequency × Wavelength
Frequency is constant,
The formula can be written as:
n = λ / λn.
Where,
λn is the wavelength in the medium
λ is the wavelength in vacuum
<u>When the light travels to glass, it speed slows down and also the wavelength decreases as both are directly proportional. There will be no effect on frequency.</u>
Answer:
length of the ladder is 13.47 feet
base of wall to latter distance 6.10 feet
angle between ladder and the wall is 26.95°
Explanation:
given data
height h = 12 feet
angle 63°
to find out
length of the ladder ( L) and length of wall to ladder ( A) and angle between ladder and the wall
solution
we consider here angle between base of wall and floor is right angle
we apply here trigonometry rule that is
sin63 = h/L
put here value
L = 12 / sin63
L = 13.47
so length of the ladder is 13.47 feet
and
we can say
tan 63 = h / A
put here value
A = 12 / tan63
A = 6.10
so base of wall to latter distance 6.10 feet
and
we say here
tanθ = 6.10 / 12
θ = 26.95°
so angle between ladder and the wall is 26.95°
The work-energy theorem states that the net work done by the forces on an object equals the change in its kinetic energy.
