Complete Image
Consider two aluminum rods of length 1 m, one twice as thick as the other. If a compressive force F is applied to both rods, their lengths are reduced by and , respectively.The ratio ΔLthick rod/ΔLthin rod is:
a.) =1
b.) <1
c.) >1
Answer:
The ratio is less than 1 i.e option B is correct
Explanation:
The Young Modulus of a material is generally calculated with this formula
Where is the stress =
is the strain =
Making Strain the subject
now in this question we are that the same tension was applied to both wires so
would be constant
Hence
for the two wire we have that
Looking at young modulus formula
Now we are told that a comprehensive force is applied to the wire so for this question
is constant
And given that the length are the same
so
Now we are told that one is that one rod is twice as thick as the other
So it implies that one would have an area that would be two times of the other
Assuming that
So
From the question the length are equal
So
Hence the ratio is less than 1
Answer:
The maximum number of bright spot is
Explanation:
From the question we are told that
The slit distance is
The wavelength is
Generally the condition for interference is
Where n is the number of fringe(bright spots) for the number of bright spots to be maximum
=>
So
substituting values
given there are two sides when it comes to the double slit apparatus which implies that the fringe would appear on two sides so the maximum number of bright spots is mathematically evaluated as
The 1 here represented the central bright spot
So
Answer: the answer i for c is yes 0& 10
Explanation:
Answer:
178.75 N
Explanation:
The force necessary to start moving the crate must be equal to or more than the frictional force (resistive force) acting on the crate but moving in an opposite direction to the frictional force.
So, we find the frictional force, Fr:
Fr = -μmg
Where μ = coefficient of friction
m = mass
g = acceleration due to gravity
The frictional force is negative because it acts against the direction of motion of the crate.
Fr = -0.57 * 32 * 9.8
Fr = - 178.75 N
Hence, the force necessary to move the crate must be at least equal to but opposite in direction to this frictional force.
Therefore, this force is 178.75 N
Answer:
2.8 cm
Explanation:
= Separation between two first order diffraction minima = 1.4 cm
D = Distance of screen = 1.2 m
m = Order
Fringe width is given by
Fringe width is also given by
For second order
Distance between two second order minima is given by
The distance between the two second order minima is 2.8 cm
Answer:
a. 409.5 m/s b. f₁ = 136.5 Hz, f₂ = 409.5 Hz, f₃ = 682.5 Hz
Explanation:
a. The speed of sound v in a gas is v = √(B/ρ) where B = bulk modulus and ρ = density. Given that on Venus, B = 1.09 × 10⁷ N/m² and ρ = 65.0 kg/m³
So, v = √(B/ρ)
= √(1.09 × 10⁷ N/m²/65.0 kg/m³)
= √(0.01677 × 10⁷ Nm/kg)
= √(0.1677 × 10⁶ Nm/kg)
= 0.4095 × 10³ m/s
= 409.5 m/s
b. For a pipe open at one end, the frequency f = nv/4L where n = mode of wave = 1,3,5,.., v = speed of wave = 409.5 m/s and L = length of pipe = 75.0 cm = 0.75 m
Now, for the first mode or frequency, n = 1
f₁ = v/4L
= 409.5 m/s ÷ (4 × 0.75 m)
= 409,5 m/s ÷ 3 m
= 136.5 Hz
Now, for the second mode or frequency, n = 2
f₂ = 3v/4L
= 3 ×409.5 m/s ÷ (4 × 0.75 m)
= 3 × 409,5 m/s ÷ 3 m
= 3 × 136.5 Hz
= 409.5 Hz
Now, for the third mode or frequency, n = 5
f₃ = 5v/4L
= 5 × 409.5 m/s ÷ (4 × 0.75 m)
= 5 × 409,5 m/s ÷ 3 m
= 682.5 Hz
Answer:
λ = hc/(eV + h)
Explanation:
Let the work function of the metal = ∅
the kinetic energy with which the electrons are ejected = E
the energy of the incident electromagnetic wave = hf
Then, we know that the kinetic energy of the emitted electron will be
E = hf - ∅
because the energy of the incident electromagnetic radiation must exceed the work function for electrons to be ejected.
This means that the energy of the incident e-m wave can be written as
hf = E + ∅
also, we know that the kinetic energy of the emitted electron E = eV
and the work function ∅ = h
we can they combine all equations to give
hf = eV + h
we know that f = c/λ
substituting, we have
hc/λ = eV + h
λ = hc/(eV + h) This is the wavelength of the e-m radiation needed to eject electrons from a metal.
where
λ is the wavelength of the e-m radiation
h is the Planck's constant = 6.63 x 10^-34 m^2 kg/s
c is the speed of e-m radiations in a vacuum = 3 x 10^8 m/s
e is the charge on an electron
V is the voltage potential on the electron
is the threshold frequency of the metal