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3 years ago

Help!?

Physics

2 answers:

Marta_Voda [28]3 years ago

3 0

Answer:

7200 m

Explanation:

The pond is 4000 meters away. The woman runs at 2.5 m/s. The time it takes her to reach the pond is:

t = 4000 m / 2.5 m/s

t = 1600 s

The dog is running at 4.5 m/s this entire time. So the distance he runs is:

d = 1600 s × 4.5 m/s

d = 7200 m

olga nikolaevna [1]3 years ago

3 0

Answer:

7200 m

Explanation:

A woman takes her pet dog on a walk to a pond which is 4km away. The woman runs with a speed of 2.5 ms-1 while the dog runs with the speed of 4.5ms^-1 towards the pond and returns to the women and then again runs back to the pond continuously until the woman also manages to reach the pond. The total distance traveled by the dog is 7200 m.

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Answer:

-100000 N.

Explanation:

Force: This can be defined as the product of the mass of a body and it's acceleration. The S.I unit of Force is Newton(N). The Formula of force is given as,

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

Where F = Average force exerted on the car, m = mass of the car, acceleration of the car, a = acceleration of the car.

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

Where v = Final velocity, u = Initial velocity, t = time.

Substitute equation 2 into equation 1

F = m(v-u)/t............. Equation 3

Given: m = 1500 kg, u = 20 m/s, v = 0 m/s (brought to rest), t = 0.3 s.

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F = 1500(-20)/0.3

F = -100000 N.

Note: The negative sign is due to the fact that the force exerted on the car by the pole is equal and opposite the force of the car.

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3 years ago

What do wind and moving water have in common? Select one: They both have electrical energy They both have elastic potential ener

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They both have kinetic energy because they are both moving and have force.
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3 years ago

According to the law of conservation of matter, we know that the total number of atoms does not change in a chemical reaction an

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Explanation:

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3 years ago

The atmospheric pressure on the top of the Engineering Sciences Building (ESB) is 97.6 kPa, while that in Room G39-ESB (ground f

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Answer:

Δ h = 52.78 m

Explanation:

given,

Atmospheric pressure at the top of building = 97.6 kPa

Atmospheric pressure at the bottom of building = 98.2 kPa

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height of the building = ?

We know,

Δ P = ρ g Δ h

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3 years ago

Suppose you pour 0.250 kg of 20.0°C water into a 0.600 kg aluminum pan off the stove with a temperature of 173°C. Assume that th

lapo4ka [179]

Answer:

$T_f=5.0116^{\circ}C$

Explanation:

Given:

mass of water, $m_w=0.25\ kg$

initial temperature of water, $T_i_w=20^{\circ}C$

initial temperature of pan, $T_i_p=173^{\circ}C$

mass of pan, $m_p=0.6\ kg$

mass of water evapourated, $m_v=0.03\ kg$

specific heat of water, $c_w=4186\ J.kg^{-1}.K^{-1}$

specific heat of aluminium pan, $c_a=900\ J.kg^{-1}.K^{-1}$

latent heat of vapourization, $L=2256000\ J.kg^{-1}$

<u>Using the equation of heat:</u>

<em>Here, initially certain mass of water is vapourised first and then the remaining mass of water comes in thermal equilibrium with the pan.</em>

$m_p.c_a.(T_{ip}-T_f)=m_v.L+(m_w-m_v).c_w.(T_f-T_{iw})$

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$T_f=5.0116^{\circ}C$

5 0

3 years ago