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2 years ago

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A bullet is fired horizontally, and at the same instant a second bullet is dropped from the same height. Ignore air resistance.

Compare the times of fall of the two bullets.

1 answer:

Brut [27]2 years ago

5 0

Answer:

They hit at the same time

Explanation:

The bullet that is fired horizontally, the horizontal component of the speed is the speed with which is its is fired and the vertical component of the speed comes in picture due to gravity only.

When the bullet is dropped from the same height, the horizontal component is zero but the vertical component arises from the gravity.

The vertical components of the velocity of both the bullets are same and thus, they fall at the same time.

<u>Answer: They hit at the same time</u>

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stealth61 [152]

Answer:

W = 9533.09 Watt

Explanation:

given,

diameter of pipe inlet, d₁ = 10 cm

r₁ = 5 cm

diameter of pipe outlet, d₂ = 15 cm

r₂= 7.5 cm

head upto water level is to rise = 60 + 5

= 65 m

flow rate = 0.015 m³/s

we know

A₁ v₁ = A₂ v₂ = Q

π r₁² v₁ = π r₂² v₂ = 0.015

$v_1= \dfrac{r_2^2}{r_1^2} v_2$

$v_1= \dfrac{7.5^2}{5^2} v_2$

$v_1= 2.25 v_2$

$v_2 = \dfrac{0.015}{\pi r_2^2}$

$v_2 = \dfrac{0.015}{\pi 0.075^2}$

v₂ = 0.848 m/s

v₁ = 1.908 m/s

Applying Bernoulli's equation

$P_p = \dfrac{1}{2}\rho (v_2^2-v_1^2)+ \rho g h$

$P_p= \dfrac{1}{2}\times 1000\times (0.848^2-1.908^2)+ 1000\times 9.8\times 65$

$P_p= 635539.32 Pa$

P_p is the pump pressure

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W = P_p x Q

W = 635539.32 x 0.015

W = 9533.09 Watt

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1 year ago

Argon in the amount of 1.5 kg fills a 0.04-m3 piston cylinder device at 550 kPa. The piston is now moved by changing the weights

Arlecino [84]

Answer:

275 kPa

Explanation:

mass of the gas=m=1.5 kg

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as the condition is given final volume is double the initial volume

V₂=final volume

V₂=2 V₁

As the temperature is constant

T₁=T₂=T

$\frac{P1V1}{T1}$ = $\frac{P2 V2}{T2}$

putting the values in the equation.

$\frac{P1V1}{T1}$ = $\frac{P2 *2V1}{T2}$

P₂= $\frac{P1}{2}$

P₂= $\frac{550}{2}$

P₂=275 kPa

So the final pressure of the gas is 275 kPa.

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2 years ago

Two movers use a rope system to lift a box to a third-story apartment. They do 1,200 J of work on the rope system, and the rope

xeze [42]

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2 years ago

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Oliga [24]

Answer:

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Explanation:

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Resistivity, $\rho=1.72\times 10^{-8}\ \Omega-m$

We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :

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or

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$B=\dfrac{\mu_o I}{2\pi r}$

$I=\dfrac{2\pi rB}{\mu_o}$

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1 year ago

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emmasim [6.3K]

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1 year ago

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