Answer:
230
Explanation:
= Rotational speed = 3600 rad/s
I = Moment of inertia = 6 kgm²
m = Mass of flywheel = 1500 kg
v = Velocity = 15 m/s
The kinetic energy of flywheel is given by
Energy used in one acceleration
Number of accelerations would be given by
So the number of complete accelerations is 230
Answer:
The newton’s second law is F=ma
The Gravitational force is
Explanation:
Given that,
The equivalent formulas for velocity, acceleration, and force using the relationships covered for UCM, Newton’s Laws, and Gravitation.
We know that,
Velocity :
The velocity is equal to the rate of position of the object.
....(I)
Acceleration :
The acceleration is equal to the rate of velocity of the object.
....(II)
Newton’s second Laws
The force is equal to the change in momentum.
In mathematically,
Put the value of p
Put the value from equation (II)
This is newton’s second laws.
Gravitational force :
The force is equal to the product of mass of objects and divided by square of distance.
In mathematically,
Where, m₁₂ = mass of first object
m= mass of second object
r = distance between both objects
Hence, The newton’s second law is F=ma
The Gravitational force is
Answer:
F = 2 × 10⁻³ N
Explanation:
Given:
frequency, f = 2400 MHz
Height, h = 25cm = 0.25 m
Area of the base, A = 30 cm x 30 cm = 900 cm² = 0.09 m²
Energy of the microwave, E = 0.50 mJ = 0.5 x 10⁻³ J
Now, the time taken by the wave from top to the base, t = h/c
here, c is the speed of the light
thus,
t = 0.25/(3 x 10⁸) = 8.33 x 10⁻¹⁰ s
The radiation pressure = Intensity/c
now, the intensity is given as:
I = Power/ area
also,
Power = Energy/ time = 0.5 x 10⁻³ J/8.33 x 10⁻¹⁰ s = 600000 W
thus,
I = 600000 W/ 0.09 m² = 6666666.6 W/m²
substituting the value in the formula for pressure due to radiation, we have
= 6666666.6 W/m²/(3 x 10⁸)
also
pressure = Force/ area
thus,
Force/ area = 6666666.6 W/m²/(3 x 10⁸)
or
Force (F) = (6666666.6 W/m² × 0.09 m²)/(3 x 10⁸)
or
F = 2 × 10⁻³ N