Answer:
35%
Explanation:
Given data
Amount of energy transferred (Input) = 270J
Amount of energy converted to sound (Output)= 94.5J
Efficiency = output/input*100
Efficiency= 94.5/270*100
Efficiency=0.35*100
Efficiency=35%
Hence the efficiency is 35%
Answer:
V = 19m/s
Explanation:
Given the following data;
Initial velocity, U = 4m/s
Acceleration, a = 0.5m/s²
Time, t = 30 seconds
To find the final velocity, we would use the first equation of motion;
V = U + at
Where;
V is the final velocity.
U is the initial velocity.
a is the acceleration.
t is the time measured in seconds.
V = 4 + 0.5*30
V = 4 + 15
V = 19m/s
Therefore, his final velocity is 19 meters per seconds.
Answer:
it depends on the appliance
Explanation:
bigger appliances will use more power, smaller appliances will use a lesser amount
Answer:
0.5 rad / s
Explanation:
Moment of inertia of the disk I₁ = 1/2 MR²
M is mass of the disc and R is radius
Putting the values in the formula
Moment of inertia of the disc I₁ = 1/2 x 100 x 2 x 2
= 200 kgm²
Moment of inertia of man about the axis of rotation of disc
mass x( distance from axis )²
I₂ = 40 x 1.25²
= 62.5 kgm²
Let ω₁ and ω₂ be the angular speed of disc and man about the axis
ω₂ = tangential speed / radius of circular path
= 2 /1.25 rad / s
= 1.6 rad /s
ω₁ = ?
Applying conservation of angular moment ( no external torque is acting on the disc )
I₁ω₁ = I₂ω₂
200 X ω₁ = 62.5 X 1.6
ω₁ = 0.5 rad / s
Answer:
12.974 m/s
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
g = Acceleration due to gravity = 9.81 m/s²
= Coefficient of friction =0.66
a = Acceleration = 
Car's original speed before braking was 12.974 m/s
