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3 years ago

Calculate the average velocity of a motor cycle that travels 72km/hr in 20 seconds

1 answer:

3 0

Velocity =displacement
Change in time
D=72km/hr
Time=20s
But the S.I unit of velocity is m/s so you woul have to change 72km/hr to m/s

Changing 72km to m

1 kilometer=1000meters
Then, 72 kilometers =?

72•1000/1
=72000m

Changing 72hours to seconds

If 1 hour = 3600 seconds
Then 72 hours=?

72•3600/1

=259200 seconds

Velocity =displacement
Change in time

V= 72,000
259,2005
=0.028m/s

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2 years ago

Which list of properties of alternation current is the most likely reason it was chosen over direct current to provide electrici

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3 years ago

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brainly.com/question/11797560
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2 years ago

In anticipation of a long 10o upgrade, a bus driver accelerates at a constant rate of 5 ft/s^2 while still on a level section of

Rashid [163]

Answer:

The distance (in miles) by the bus up the hill when its speed decreased to 50 mph is approximately 1.353 miles

Explanation:

The parameters of the motion of the driver are;

The upgrade of the road, θ = 10°

The rate of constant acceleration of the bus driver = 5 ft./s²

The speed of the bus as it begins to go up the hill, v₁ = 80 mph = 117.3228 ft./s

The speed of the driver at a point on the hill, v₂ = 50 mph ≈ 73.32677 ft./s

The acceleration due to gravity, g ≈ 32.1740 ft./s²

Therefore, we have;

The acceleration due to gravity down the incline plane, gₓ = g·sinθ

∴ gₓ = g·sin(θ) ≈ 32.1740 ft./s² × sin(10°) ≈ 5.587 ft/s²

The net acceleration of the bus, on the incline plane, $a_{Net}$ = gₓ - a = 5.587 ft./s² -5 ft./s² = 0.587 ft./s²

The vertical component of the velocity, $v_y$ = v × sin(θ)

∴ $v_y$ = 117.3228 ft./s × sin(10°) ≈ 20.37289 ft./s

vₓ = 117.3228 ft./s × cos(10°) ≈ 115.5404 ft./s

The velocity of the car, v₂, on the inclined plane is given as follows;

v₂ = v₁ - $a_{Net}$ × t

∴ t = (v₁ - v₂)/ $a_{Net}$ = (117.3228 ft./s - 73.32677 ft./s)/(0.587 ft./s²) ≈ 74.95 s

The distance covered, 's', is given as follows;

s = v₁·t - 1/2· $a_{Net}$ ·t²

∴ s = 117.3228 × 74.95 - 1/2 × 0.587 × 74.95² ≈ 7144.6069 ft.

The distance travelled up the hill, s ≈ 7144.6069 ft. ≈ 1.3531452 miles ≈ 1.353 miles

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3 years ago