Answer:
a = 9.94 m/s²
Explanation:
given,
density at center= 1.6 x 10⁴ kg/m³
density at the surface = 2100 Kg/m³
volume mass density as function of distance
r is the radius of the spherical shell
dr is the thickness
volume of shell
mass of shell
now,
integrating both side
we know,
a = 9.94 m/s²
Answer: D
Wavelength λ = 7.5 × 10^-11 m
Explanation:
You are given the frequency of an electromagnetic wave to be:
F = 4.0 x 1018 Hz. And the speed of light C to be
C = 3 × 10^8 m/s
From wave speed formula:
Wave speed is the product of waves frequency and wavelength. That is,
V = fλ
Where
f = frequency
λ = wavelength
V = C = speed of light
Substitute the values of the parameters into the formula
C = fλ
3 × 10^8 = 4 × 10^18 × λ
Make λ the subject of formula
λ = (3×10^8)/(4×10^18)
λ = 7.5 × 10^-11 m
Therefore, the wavelength of the wave is 7.5 × 10^-11 m
The answer is c. Hope that helped
Answer:
A
Explanation:
When two magnets are brought near each other, like poles repel; opposite poles attract. We like to represent this force effect of a magnet on iron-like objects with a concept called magnetic field. The concept of field can be best understood if we remember the gravitational force of Earth on object near it.
Answer:
Acceleration is -1.2 m/s² and distance covered is 135 m.
Explanation:
A train going at a speed of 18m / s brakes and stops in 15s calculates its acceleration and the distance traveled when braking
Given that,
The initial speed of the train, u = 18 m/s
Final speed, v = 0
Time, t = 15 s
We need to find acceleration and distance traveled when braking. Let a is acceleration and distance traveled.
Acceleration,
Using third equation of motion,
Hence, acceleration is -1.2 m/s² and distance covered is 135 m.