Option (a) is correct.
Falling objects accelerate as they approach the ground.This is because of the force of gravity acting on the falling objects. so the velocity of these objects increases continuously as they approach the ground. the acceleration acting on the falling objects is a constant ( close to the surface of earth) and is called as acceleration due to gravity denoted by g. value of g=9.8 m/s².
Answer:
The amplitude of vibration of string will increase due to which loudness of sound will increase
Explanation:
As we know that the guitar is based on the principle of Resonance. When string of the guitar vibrates at a given frequency then the sound produced in the hollow part of the guitar will also be at same frequency.
This is known as resonance condition, so guitar will produce same frequency sound as that of frequency of string.
Now if the string is plucked with increasing level of force then it will increase the amplitude of vibrations of the string due to which the sound produced in the guitar will also be of same level.
So here we can say that amplitude and intensity of sound related as

so on increasing amplitude the intensity will increase and hence it will produce loud sound
Answer:
The magnetic field is
Explanation:
From the question we are told that
The mass of the metal rod is 
The current on the rod is 
The distance of separation(equivalent to length of the rod ) is 
The coefficient of kinetic friction is 
The kinetic frictional force is 
The constant speed is 
Generally the magnetic force on the rod is mathematically represented as

For the rod to move with a constant velocity the magnetic force must be equal to the kinetic frictional force so

=> 
=> 
=> 
Answer:
0.0334N
Explanation:
Given parameters:
M1 = 5 x 10⁶kg
M2 = 1 x 10⁶kg
Distance = 100m
Unknown:
Gravitational force = ?
Solution:
To solve this problem, we use the Newton's law of universal gravitation.
Fg =
G is the universal gravitation constant
m is the mass
r is the distance
Fg =
= 0.0334N
Answer:
E. two times the original diameter
Explanation:
Resistance of a wire is:
R = ρ L/A
where ρ is the resistivity of the material, L is the length, and A is the cross-sectional area.
For a round wire with diameter d:
R = ρ L / (¼ π d²)
The two wires must have the same resistance, so:
ρ₁ L₁ / (¼ π d₁²) = ρ₂ L₂ / (¼ π d₂²)
The wires are made of the same material, so ρ₁ = ρ₂:
L₁ / (¼ π d₁²) = L₂ / (¼ π d₂²)
The new length is four times the old, so 4 L₁ = L₂:
L₁ / (¼ π d₁²) = 4 L₁ / (¼ π d₂²)
1 / (¼ π d₁²) = 4 / (¼ π d₂²)
Solving:
1 / (d₁²) = 4 / (d₂²)
(d₂²) / (d₁²) = 4
(d₂ / d₁)² = 4
d₂ / d₁ = 2
So the new wire must have a diameter twice as large as the old wire.