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3 years ago

An egg is dropped from a building that is 61 m high.

Physics

1 answer:

Allisa [31]3 years ago

3 0

Answer:

Initial Velocity = 0 m/s

Final Velocity = 34.6 m/s

time = 3.5 s

Explanation:

The initial velocity must be zero since, the egg must be at rest initially, before dropping.

<u>Initial Velocity = 0 m/s</u>

Now, for time we use 2nd equation of motion:

h = Vi t + (1/2)gt²

where,

h = Height = 61 m

Vi = Initial Velocity = 0 m/s

g = 9.8 m/s²

t =time = ?

Therefore,

61 m = (0 m/s)(t) + (1/2)(9.8 m/s²)t²

t² = (61 m)(2)/(9.8 m/s²)

t = √(12.45 s²)

Now, for final velocity we will use 1st equation of motion:

Vf = Vi + gt

Vf = 0 m/s + (9.8 m/s²)(3.5 s)

Vf = 34.6 m/s

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A ball is launched from the ground with a horizontal speed of 30 m/s and a vertical speed of 30 m/s. What will the horizontal sp

gulaghasi [49]

Answer:

Explanation:

horizintal speed stays same

only vertical speed changes

so H speed will stay 30 m/s

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3 years ago

How far would a horse that rides at 5.5 m/s travel in 6.3 minutes?

larisa [96]

Answer: d = 2,079 m

Explanation:

5.5 m/s(6.3 min)(60 s/min) = 2,079 m

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3 years ago

Short Answer Questions:

Otrada [13]

According to Archimede's principle, a physical object experiences an upthrust due to a difference in pressure between upper and lower surfaces.

<h3>What is an upthrust?</h3>

An upthrust is also referred to as buoyancy and it can be defined as an upward force which is exerted by a fluid (liquid or gas), so as to oppose the weight of a partially or fully immersed physical object that is floating in it.

Based on scientific information, a physical object experiences an upthrust when it is immersed in a fluid due to a difference in height and pressure between upper (top) and lower (bottom) surfaces.

According to Archimede's principle, there is a higher pressure at the bottom of the physical object due to height, and a lower pressure at the top of the physical object.

Read more on upthrust here: brainly.com/question/24389514

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4 0

2 years ago

Reading glasses with a power of 1.50 diopters make reading a book comfortable for you when you wear them 1.8 cmcm from your eye.

Vlad1618 [11]

Answer:

The near point is $n =44.8 \ cm$

Explanation:

From the question we are told that

The power is $P = 1.50$

The distance from the eye is $k = 1.8 \ cm$

The distance of the book from the eye is $z = -28 \ cm$

Generally the focal length of the glasses is

$f = \frac{1}{P}$

=> $f = \frac{1}{1.50 }$

=> $f = 0.667 \ m$

=> $f = 66.7 \ cm$

The object distance is evaluated as

$u = z + k$

=> $u = -28 + 1.8$

=> $u = -26.2 \ cm$

The image distance is evaluated from lens formula as

$\frac{1}{v} = \frac{1}{f} + \frac{1}{u}$

=> $\frac{1}{v} = \frac{1}{66.7} + \frac{1}{-26.2}$

=> $v=- \frac{1}{0.0232}$

=> $v=- 43 \ cm$

The near point is evaluated as

$n = -v + k$

=> $n =-(-43) + 1.8$

=> $n =44.8 \ cm$

3 0

3 years ago

What is the amount of thermal energy needed to make 5 kg of ice at - 10 °C to

agasfer [191]

Answer:

The amount of thermal energy needed is 15167500 joules.

Explanation:

By First Law of Thermodynamics, we see that amount of thermal energy ( $Q$ ), in joules, is equal to the change in internal energy. From statement we understand that change in internal energy consisting in two latent components ( $U_{l,ice}$ , $U_{l,steam}$ ), in joules, and two sensible component ( $U_{s,w}$ ), in joules, that is:

$Q = U_{l,ice} + U_{s, w} + U_{s,ice} + U_{l,steam}$ (1)

By definitions of Sensible and Latent Heat, we expanded the formula:

$Q = m\cdot (h_{f,w}+h_{v,w}+c_{ice}\cdot \Delta T_{ice}+c_{w}\cdot \Delta T_{w})$ (2)

Where:

$m$ - Mass, in kilograms.

$h_{f,w}$ - Latent heat of fussion of water, in joules per kilogram.

$h_{v,w}$ - Latent heat of vaporization of water, in joules per kilogram.

$c_{ice}$ - Specific heat of ice, in joules per kilogram per degree Celsius.

$c_{w}$ - Specific heat of water, in joules per kilogram per degree Celsius.

$\Delta T_{ice}$ - Change in temperature of ice, measured in degrees Celsius.

$\Delta T_{w}$ - Change in temperature of water, measured in degrees Celsius.

If we know that $m = 5\,kg$ , $h_{f,w} = 3.34\times 10^{5}\,\frac{J}{kg}$ , $h_{v,w} = 2.26\times 10^{6}\,\frac{J}{kg}$ , $c_{ice} = 2.090\times 10^{3}\,\frac{J}{kg\cdot ^{\circ}C}$ , $c_{w} = 4.186\times 10^{3}\,\frac{J}{kg\cdot ^{\circ}C}$ , $\Delta T_{ice} = 10\,^{\circ}C$ and $\Delta T_{w} = 100\,^{\circ}C$ , then the amount of thermal energy is:

$Q = 15167500\,J$

The amount of thermal energy needed is 15167500 joules.

7 0

3 years ago