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2 years ago

5. How many kilowatt-hours of energy would be used by a 40 W bulb that runs for 10 hours every

Physics

1 answer:

Nady [450]2 years ago

6 0

Answer:

E = 0.4 kWh

Explanation:

Given that,

The power of a bulb, P = 40 W

Time, t = 10 hours

We need to find the energy used by the bulb. Let it is equal to E. So,

$E=P\times t\\\\E=40\times 10\\\\E=400\ W-h\\\\or\\\\E=0.4\ kWh$

So, 0.4 kWh of energy would be needed.

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Your heart pumps 80 g of blood with each beat. The blood starts from rest and reaches a speed of 0.60 m/s in the aorta. If each

Gala2k [10]

Answer:

d. 0.3 N

Explanation:

Force: This is defined as the product of mass of a body and its acceleration.

The S.I unit of Force is Newton (N).

Mathematically Force can be represented as,

F = ma .................. Equation 1

Where F = force, m = mass, a = acceleration.

also

a = (v-u)/t............... Equation 2

Where v = final velocity, u = initial velocity, t = time.

Given: v = 0.60 m/s, u = 0 m/s ( From rest), t= 0.16 s.

Substitute into equation 2

a = (0.60-0)/0.16

a = 3.75 m/s²

Also given: m = 80 g = 0.08 kg.

Substitute into equation 1,

F = 0.08(3.75)

F = 0.3 N.

Hence he average force = 0.3 N

The right option is d. 0.3 N

6 0

3 years ago

9. What is the equivalent resistance of the circuit shown in the figure below?

user100 [1]

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4 0

2 years ago

The Answer to the question is plant cell. I got this wrong...Thanks Alot

Scilla [17]

This is a statement not a question .

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3 years ago

A boy threw a ball upward and it took 3 sec to reach the highest point. Determine the initial velocity of the ball.

makkiz [27]

Answer:

V initial = 29.4 m.s²

Explanation:

( Using the laws of motion)

V final = V initial + Acceleration × time

0 = V initial + ( -9.8)(3)

29.4 = V initial

* I took upward as positive that's why I substituted -9.8 *

* for V final we know that at maximum height the ball is not moving thats why is = 0 *

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1 year ago

When an electric current is flowing through a wire, the force deflecting the charged particles is the greatest when the wire is

Makovka662 [10]

The force is greatest when the wire is perpendicular to the magnetic field.

In fact, the expression for the magnetic force is
$F=ILB \sin \theta$
where I is the current, L the length of the wire, B the magnetic field intensity and $\theta$ is the angle between the directions of I and B.

We can see that F is maximum when $\sin \theta=1$ , so when $\theta = 90^{\circ}$ , so when the wire and the magnetic field are perpendicular to each other.

5 0

2 years ago

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