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2 years ago

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A car travels 50 km in 25 km /h and then travels 60km with a velocity 20 km/h and then travels 60km with a velocity 20 km/h in t

he same direction. Find the velocity

1 answer:

Butoxors [25]2 years ago

3 0

Answer:

v = 21.25 km/h

The average velocity is 21.25km/h

Explanation:

Average velocity = total displacement/time taken

v = d/t

Given;

A car travels 50 km in 25 km /h

d1 = 50km

v1 = 25km/h

time taken = distance/velocity

t1 = d1/v1

t1 = 50/25 = 2 hours

and then travels 60km with a velocity 20 km/h

d2 = 60km

v2 = 20km/h

t2 = d2/v2 = 60/20

t2 = 3 hours

and then travels 60km with a velocity 20 km/h in the same direction

d3 = 60km

v3 = 20km/h

t3 = d3/v3 = 60/20

t3 = 3 hours

Average velocity = total displacement/total time taken

v = (d1+d2+d3)/(t1+t2+t3)

v = (50+60+60)/(2+3+3)

v = 170/8

v = 21.25 km/h

The average velocity is 21.25km/h

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Explanation:

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3 years ago

A sphere of mass of 1.55 kg is accelerated upwards by a string to which the sphere is attached. Its speed increases from 2.81 m/

Mama L [17]

Answer:

The tension in the string is 16.24 N

Explanation:

Given;

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final velocity of the sphere, v = 4.60 m/s

duration of change in the velocity, Δt = 2.64 s

The tension of the string is calculated as follows;

$T = ma + mg\\\\T = m(a + g)\\\\where;\\\\a \ is \ upward \ acceleration \ of \ the \ sphere\\\\g \ is \ acceleration \ due \ to \ gravity =9.8 \ m/s^2\\\\a = \frac{\Delta V}{\Delta t} = \frac{v- u}{ t} = \frac{4.6 - 2.81 }{2.64} = 0.678 \ m/s^2$

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Explanation:

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2 years ago

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A jet aircraft is traveling at 262 m/s in horizontal flight. The engine takes in air at a rate of 85.9 kg/s and burns fuel at a

Fittoniya [83]

Answer:

$F_T=60132.52N$

$P=15814852.76W$

Explanation:

From the question we are told that

Velocity of aircraft $V=263m/s$

Engine air intake rate $\triangle M_a=85.9kg/s$

Fuel burn rate $\triangle M_f =3.92kg/s$

Velocity of exhaust gas $V_e =921m/s$

Generally the Mass change rate of Rocket is mathematically given by

$\triangle M = \triangle M_a+\triangle M_f$

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$\triangle M=89.82kg/s$

Generally the Trust of the rocket is given mathematically by

$F_T=(\triangle M *V_e)-(dM_a/dt)*(V)$

$F_T=(89.82 *921)-(85.9)*(263)$

$F_T=60132.52N$

Generally the Rocket's delivered power is mathematically given by

Delivered power P

$P=V*F_T$

$P=263*60132.52N$

$P=15814852.76W.$

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2 years ago