Answer:
21
Explanation: its actually 20.85 but i guess they round to 21
Answer:
6.3445×10⁻¹⁶ m
Explanation:
E = Accelerating voltage = 2.47×10³ V
m = Mass of electron
Distance electron travels = 33.5 cm = 0.335 cm

Deflection by Earth's Gravity

Now, Time = Distance/Velocity

∴ Magnitude of the deflection on the screen caused by the Earth's gravitational field is 6.3445×10⁻¹⁶ m
The correct answer to the question is : 1) Converting energy and 2) Within about twenty years, natural gas forms.
EXPLANATION:
In coal fired power plants, the water is heated by burning coals. The heat produced in this process will convert water into steam. The steam is allowed to rotate the turbine. The turbine is attached to a generator which converts the kinetic energy of the steam into electric energy due to electromagnetic induction.
Hence, turbine helps in converting energy.
As per the second question, Walt listed the steps that occur during the formation of natural gas.
The natural gas is produced due to natural phenomenon. For this, millions of years are passed. So, it is a long range process in which the fossil of animals and planets buried beneath the surface are converted into natural gas under high pressure.
Hence, the mistake of Walt is that the natural gas is produced withing twenty years.
Answer:
The car traveled the distance before stopping is 90 m.
Explanation:
Given that,
Mass of automobile = 2000 kg
speed = 30 m/s
Braking force = 10000 N
For, The acceleration is
Using newton's formula

Where, f = force
m= mass
a = acceleration
Put the value of F and m into the formula

Negative sing shows the braking force.
It shows the direction of force is opposite of the motion.


For the distance,
Using third equation of motion

Where, v= final velocity
u = initial velocity
a = acceleration
s = stopping distance of car
Put the value in the equation


Hence, The car traveled the distance before stopping is 90 m.
Answer:
Stress = 4.67 * 10^-7 N/m²
Explanation:
Young's modulus of the material = Stress/Strain
Given
Young's modulus = 228 x 10^9 Pa
Stress = 106,483 Pa
Required
Strain
From the formula;
Strain = Stress/Young modulus
Strain = 106,483 /228 x 10^9
Stress = 4.67 * 10^-7 N/m²