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4 years ago

ASAPPP

Physics

2 answers:

katen-ka-za [31]4 years ago

8 0

Power is the rate at which work is done (2nd option)

frozen [14]4 years ago

5 0

Answer:

Power is the rate at which work is done.

Explanation:

The work done divided by total time taken is called power of an object. The SI unit of power is watts. It is denoted by W. Its expression is given by :

$P=\dfrac{W}{t}$

Since, W = F.d

$P=\dfrac{F\times d}{t}$

Since, $\dfrac{d}{t}=v$

$P=F\times v$

It is also equal to the product of force and velocity. Hence, the correct option is (c).

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A bird flies from the south pole to the north pole. Part of the journey is 1000 miles that takes two weeks. What is the birds Ve

alexira [117]

Formula for Velocity = DISTANCE traveled/TIME to travel distance + direction

For this one, we can use mph(miles per hour) as unit.

v = 1,000 miles / 336 hours (2 weeks = 24 hours x 14 days = 336 hrs)
= 2.98 mph North

or we can use kph (kilometers per hour)

v = 1609.34 km / 336 hours (1 mile = 1.60934 km)
= 4.79 kph North

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3 years ago

Consider a completely elastic head-on collision between two particles that have the same mass and the same speed. What are the v

motikmotik

Answer:

The magnitude of their velocities will be the same but their direction will be reversed.

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4 years ago

A train travels 90 kilometers in 1 hour, and then 82 kilometers in 5 hours. What is it’s average speed?

PIT_PIT [208]

Distance is 90km,time 1 hr
distance 2 is 82km,time 5 hrs
average speed=total distance travelled/total time taken.
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average speed=28.7km over hour

4 0

3 years ago

The index of refraction of a clear plastic is listed as 1.89 in the book, but you measured the angle of incidence 63.5° and the

lakkis [162]

Answer:

<h2>index of refraction = 1.69</h2><h2>percentage error = 10.58%</h2>

Explanation:

According to Snell's law, the ratio of the sine of angle of incidence to the sine of angle of refraction is a constant for a given pair of media. The constant is known as the refractive index.

Mathematically $\frac{sin i}{sin r} = n$

i = angle of incidence measured = 63.5°

r = angle of refraction measured = 32°

n = refractive index

$n = \frac{sin 63.5^{0} }{sin 32^{0} } \\n = \frac{0.8949}{0.5299}\\ n = 1.69$

The index fraction calculated is approx. 1.69.

If the index of refraction of a clear plastic as listed in the book is 1.89 and the calculated is 1.69, the percentage error will be calculated as thus;

%error = $\frac{1.89-1.69}{1.89} * 100$

%error = $\frac{0.2}{1.89}*100$

%error = $\frac{20}{1.89}$

%error = 10.58%

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4 years ago

According to Newton's first law, if an object is slowing down, what must be happening?A.No forces are acting on it.

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According to Newton's first law of motion, if the net force acting on an object is zero, the object remains at rest, or if the object is already moving, continues to move in a straight line with constant speed. Galileo realized the motion of an object doesn't change until an unbalanced force acts on it.

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3 years ago

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