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3 years ago

imagine a horse pulling a cart. What would happen to the speed of the cart if several bags of cement were adding to the cart?

2 answers:

iogann1982 [59]3 years ago

7 0

Assuming the power delivered by the horse does not change, the speed of the cart will decrease.
In fact, the power delivered by the horse is the work done by the horse (W) per unit time (t):
$P=\frac{W}{t}$
If several bags are added to the cart, the horse must do more work to transport them. Therefore, W in the fraction increases. But if the power P of the horse is constant, then it means that the time t must increase as well. So, the horse will take more time to transport the car, and this means that the speed of the cart has decreased.

boyakko [2]3 years ago

4 0

Answer:

Horse will become slower as we add more number of bags on the trolley

Explanation:

If a horse is pulling the cart then here horse must have to apply sufficient force on the cart so that the applied force is just counterbalancing the friction force on cart.

Now here we know that friction force is given as

$F_f = \mu mg$

where

m = total mass of the cart

Now if we assume here that horse will is giving constant power to the cart

so we will have

$P = F.v$

Power is given as product of applied force by horse on cart and its velocity

now as we know that if we put more bags on the cart then it will increase the weight of cart.

Due to increase in weight of cart there will be more friction force on it so horse must have to apply more force to counterbalance the friction force.

Now in order to maintain constant power velocity of horse must have decrease.

So horse will become slower as we add more number of bags on the trolley

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seraphim [82]

(a) Determine the circumference of the Earth through the equation,
C = 2πr
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C = 2π(1.50 x 10¹¹ m)
C = 9.424 x 10¹¹ m

Then, divide the answer by time which is given to a year which is equal to 31536000 s.
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3 years ago

Would water molecules in Venus’ atmosphere, whose temperature is 740 K, escape into outer space? A water molecule has a mass tha

Akimi4 [234]

Answer:

The water molecule cannot escape, since the average velocity of the water molecules is less than one sixth of the escape velocity of venus.

Explanation:

The average speed of gas molecules is given by:

$v_{rms}=\sqrt{\frac{3RT}{M}}$

R is the gas constant, T is the temperature and M the molar mass of the gas.

We know that a water molecule has a mass that is 18 times that of a hydrogen atom:

$M_H=1.01*10^{-3}\frac{kg}{mol}\\M_{H2O}=18M_H=0.02\frac{kg}{mol}$

So, we have:

$v_{rms}=\sqrt{\frac{3(8.314\frac{J}{mol \cdot K})740K}{0.02\frac{kg}{mol}}}\\v_{rms}=960.65\frac{m}{s}*\frac{1km}{1000m}=0.96\frac{km}{s}$

The water molecule cannot escape, since the average velocity of the water molecules is less than one sixth of the escape velocity of venus:

$10\frac{km}{s}*\frac{1}{6}=1.6\frac{km}{s}\\0.96\frac{km}{s}$

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3 years ago

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The answer is yes

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3 years ago

Over a span of 6.0 seconds, a car changes it's speed from 89 km/h to 37 km/h. What is its average acceleration in meters per sec

scoundrel [369]

Acceleration = (change in speed) / (time for the change)

change in speed = (speed at the end) - (speed at the beginning)

change in speed = (37 km/hr) - (89 km/hr) = -52 km/hr

Acceleration = (-52 km/hr) / (6 sec)

Acceleration = (-26/3) km/(hr·sec)

Units: (1/hr·sec) · (hr/3600 sec) = 1 / 3600 sec²

(-26/3) km/(hr·sec) = (-26/3) km/(3600 sec²)

= -26,000/(3 · 3600) m/s²

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3 years ago

Physics B 2020 Unit 3 Test

weqwewe [10]

Answer:

When a charge is in motion in a magnetic field, the charge experiences a force of magnitude

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$f=\frac{qB}{2\pi m}$

where here:

$q=1.602\cdot 10^{-19}C$ is the charge of the electron

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$m=9.31\cdot 10^{-31} kg$ is the mass of the electron

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