Answer:
A) Kinetic
Explanation:
Kinetic friction is friction caused by motion. Kinetic energy is energy in motion.
Ω₀ = the initial angular velocity (from rest)
t = 0.9 s, time for a revolution
θ = 2π rad, the angular distance traveled
Let
α = the angular acceleration
ω = the final angular velocity
The angular rotation obeys the equation
(1/2)*(α rad/s²)*(0.9 s)² = (2π rad)
α = 15.514 rad/s²
The final angular velocity is
ω = (15.514 rad/s²)*(0.9 s) = 13.963 rad/s
If the thrower's arm is r meters long, the tangential velocity of release will be
v = 13.963r m/s
Answer: 13.963 rad/s
Answer:
The mass of the object, its acceleration due to gravity and the distance between the top of the hill and the ground level.
Explanation:
gravitational potential energy is the energy possessed by a body under influence of gravitational force by virtue of its position.
In order to determine the gravitational potential energy of the brick, we must know the mass (m) of the brick, its acceleration due to gravity (g) since it is acting under the influence of gravitational force and the distance between the top of the hill and the ground level. (The height).
Potential energy of a body is calculated as mass × acceleration due to gravity × height.
Answer:
The lenses with different focal length are four.
Explanation:
Given that,
Radius of curvature R₁= 4
Radius of curvature R₂ = 8
We know ,
Refractive index of glass = 1.6
When, R₁= 4, R₂ = 8
We need to calculate the focal length of the lens
Using formula of focal length

Put the value into the formula



When , R₁= -4, R₂ = 8
Put the value into the formula



When , R₁= 4, R₂ = -8
Put the value into the formula



When , R₁= -4, R₂ = -8
Put the value into the formula



Hence, The lenses with different focal length are four.
Answer:
Explanation:
Velocity of a wave is describe as
velocity =Frequency × Wavelength
Mathematically
v = fλ
Hence, Frequency, F = v / λ
Wavelength λ = v/f
So, if the frequency is kept constant, wavelength of the wave becomes directly proportional to velocity of the wave.
And this implies that, as the speed double, the wavelength is double.