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3 years ago

5

Mr. Mann explained that when light passes from air into the water, the light waves bend, or ___________, and the pencil appears

to be broken.

1 answer:

posledela3 years ago

4 0

Answer:

the light waves bend or REFRACT

Explanation:

You might be interested in

What is the meaning of anything

larisa86 [58]

Answer:

everything

Explanation:

Used to refer to a thing, no matter what

4 0

3 years ago

An automobile traveling 95 km/h overtakes a 1.30-km-long train traveling in the same direction on a track parallel to the road.

SCORPION-xisa [38]

Answer: 6.175 km

Explanation:

from the question, we have the following

velocity of the automobile = 95 km/g

velocity of the train = 75 km/h

length of the train = 1.30 km

since the automobile and the train are moving in the same direction, we need to find the velocity of the car relative to the train which will be their difference in speed = 95 - 75 = 20 km/h

we need to find the time it takes the automobile to overtake the train using the formula time = distance / speed , with the distance being the length of the train.

time (t) = 1.3 / 20

= 0.065 hour

now we can find the distance traveled by the automobile using the the time taken for it to overtake the train and the speed of the automobile.

therefore, distance = speed x time

distance = 95 x 0.065 =6.175 km

5 0

4 years ago

A student pushes a 40-N block across the floor for a distance of 10 m. How much work was applied to move the block? A. 4 J B. 40

damaskus [11]

Now for this problem, what is given is a 40 Newtons which would represent the force to be applied to the object, and a distance of 10 meters after the application of the said force. When these two combine, work is done. The unit for work is Joules and this is what we are looking for. The formula to get Joules or for work would be the force applied to the object multiplied by the distance that it travelled after the application of the force. It looks like this

work = force x distance
Joules = Newtons x meter

so let us substitute the variables to their corresponding places

Joules = 40 N x 10 m
Joules = 400 J

So the answer to this question would be C. 400 J

7 0

3 years ago

Read 2 more answers

A heat engine accepts 200,000 Btu of heat from a source at 1500 R and rejects 100,000 Btu of heat to a sink at 600 R. Calculate

diamong [38]

To solve the problem it is necessary to apply the concepts related to the conservation of energy through the heat transferred and the work done, as well as through the calculation of entropy due to heat and temperatra.

By definition we know that the change in entropy is given by

$\Delta S = \frac{Q}{T}$

Where,

Q = Heat transfer

T = Temperature

On the other hand we know that by conserving energy the work done in a system is equal to the change in heat transferred, that is

$W = Q_{source}-Q_{sink}$

According to the data given we have to,

$Q_{source} = 200000Btu$

$T_{source} = 1500R$

$Q_{sink} = 100000Btu$

$T_{sink} = 600R$

PART A) The total change in entropy, would be given by the changes that exist in the source and sink, that is

$\Delta S_{sink} = \frac{Q_{sink}}{T_{sink}}$

$\Delta S_{sink} = \frac{100000}{600}$

$\Delta S_{sink} = 166.67Btu/R$

On the other hand,

$\Delta S_{source} = \frac{Q_{source}}{T_{source}}$

$\Delta S_{source} = \frac{-200000}{1500}$

$\Delta S_{source} = -133.33Btu/R$

The total change of entropy would be,

$S = \Delta S_{source}+\Delta S_{sink}$

$S = -133.33+166.67$

$S = 33.34Btu/R$

Since $S\neq 0$ the heat engine is not reversible.

PART B)

Work done by heat engine is given by

$W=Q_{source}-Q_{sink}$

$W = 200000-100000$

$W = 100000 Btu$

Therefore the work in the system is 100000Btu

4 0

4 years ago

A 7.7cm length of straight wire run horizontally along a north south line . The wire carries a 3.45 current flowing northward th

Maurinko [17]

Answer:

F = 0.332 N in the east direction

Explanation:

Length, L = 7.7 cm = 7.7 * 0.01 = 0.077 m(along the north south)

Current, I = 3.45 A (northwards)

Magnetic field, B = 1.25 T (vertically upwards)

The magnitude of the force is given by, F = ILBsin90

F = 3.45 * 0.077 * 1.25 * 1

F = 0.332 N

The direction of the force is calculated using the Right Hand Thumb Rule:

It states that "Hold the wire carrying current in your right hand so that the thumb points along the wire in the direction of the current, then the fingers will encircle the wire in the direction of the lines of magnetic force."

Based on the Right Hand Thumb Rule, the magnetic force will act in the east direction

3 0

3 years ago