Concept:
Frequency- It is defined as the number of oscillations occur in one second.
Its SI unit is Hertz (Hz)
Given: Produced sound vibrations is 18,500 cycles in 0.75 seconds
∵ In 0.75 second, produced sound has oscillations = 18,500 cycles
∴ In 1.0 second, produced sound has oscillations = (18,500 ÷ 0.75) Hz
The frequency of the sound will be ≈ 24,667 Hz
From the study of the given graph, only the animals (c) Cats, (b) Moths and (a) Bats can hear the produced sound because their upper audible frequency range is greater than 24,667 Hz.
The power of a machine is the work/time ratio for that particular machine
Its the rate of doing work.
Answer:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
Explanation:
The general kinematic equation for horizontal displacement is gives as:
Δx = v₀t + (1/2)at²
Where
Δx = change in the x direction
v₀ = initial velocity
t = time
a = acceleration
If the body is vertically instead of horizontally, Δx is changed to Δy
Δy = v₀t + (1/2)at²
For a vertical moving body, the acceleration it experiences is the gravitational accerelation of the earth 'g'
So the equation becomes:
Δy = v₀t + (1/2)gt²
where g = 9.81 m/s if the body is moving downwards and g = -9.81 m/s if the body is moving upwards
Answer: D
Explanation: Resistance of current in a wire is directly proportional to the length of the wire and inversely proportional to the cross - sectional area of the wire. That is,
R = (rho × L)/A
Where
L = length of the wire
A = cross sectional Area of the wire
rho = resistivity = proportionality constant which depends on the quality of the wire.
Therefore, Resistance and resistivity are related by a:
proportionality constant dependent on the identity of the material.
