Answer:
<u>The correct answer is 0.556 Watts</u>
Explanation:
The computer monitor uses 200 Watts of power in an hour, that is the standard measure.
If we want to know, how much energy the computer monitor uses in one second, we will have to divide both sides of the equation into 3,600.
1 hour = 60 minutes = 3,600 seconds (60 x 60)
Energy per second = 200/3600
Energy per second = 0.0556 Watts
Therefore to calculate how much energy is used in 10 seconds, we do this:
Energy per second x 10
<u>0.0556 x 10 = 0.556 Watts</u>
<u>The computer monitor uses 0.556 Watts in 10 seconds</u>
For this, you need the v-squared equation, which is v(final)² = v(initial)² + 2aΔx
The averate acceleration is thus a = (v(final)² - v(initial)²) / 2Δx = (20² - 15²) / 2(50) = 175 / 100 = 1.75 m/s²
So the average acceleration is 1.75 m/s²
Answer:
change of momentum does not depend on the mass of the cars, as the force and time are the same all vehicles have the same change of momentum
Explanation:
Let's look for the speed of the car
F = m a
a = F / m
We use kinematics to find lips
v = v₀ + a t
v = v₀ + (F / m) t
The moment is defined by
p = m v
The moment change
Δp = m v - m v₀
Let's replace the speeds in this equation
Δp = m (v₀
+ F / m t) - m v₀
Δp = m v₀ + F t - m v₀
Δp = F t
We see that the change of momentum does not depend on the mass of the cars, as the force and time are the same all vehicles have the same change of momentum
Answer:
The correct answer is B
Explanation:
Let's calculate the electric field using Gauss's law, which states that the electric field flow is equal to the charge faced by the dielectric permittivity
Φ
= ∫ E. dA = 
/ ε₀
For this case we create a Gaussian surface that is a sphere. We can see that the two of the sphere and the field lines from the spherical shell grant in the direction whereby the scalar product is reduced to the ordinary product
∫ E dA = / ε₀
The area of a sphere is
A = 4π r²
E 4π r² = / ε₀
E = (1 /4πε₀
) q / r²
Having the solution of the problem let's analyze the points:
A ) r = 3R / 4 = 0.75 R.
In this case there is no charge inside the Gaussian surface therefore the electric field is zero
E = 0
B) r = 5R / 4 = 1.25R
In this case the entire charge is inside the Gaussian surface, the field is
E = (1 /4πε₀
) Q / (1.25R)²
E = (1 /4πε₀
) Q / R2 1 / 1.56²
E₀ = (1 /4π ε₀
) Q / R²
= Eo /1.56
²
= 0.41 Eo
C) r = 2R
All charge inside is inside the Gaussian surface
=(1 /4π ε₀
) Q 1/(2R)²
= (1 /4π ε₀
) q/R² 1/4
= Eo 1/4
= 0.25 Eo
D) False the field changes with distance
The correct answer is B
Explanation: Newton's first law of motion states that a body at rest remains at rest, or, if in motion, remains in motion at a constant velocity unless acted on by a net external force. This is also known as the law of inertia. Inertia is the tendency of an object to remain at rest or remain in motion.
