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3 years ago

Is it possible to do work on an object that remains at rest ?

1 answer:

4 0

Is it possible to do work on an object that remains at rest? Work requires that a force acts over a distance. If an object does not move at all, there is no displacement, and therefore no work done.

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Tech A says a camshaft position sensor must be positioned correctly to accurately signal the position of the camshaft to the pow

qaws [65]

Answer:

Both Tech A and Tech B

Explanation:

It's important to position sensor accurately to the position of camshaft to the powertrain control in the ignition module as said by Tech A. Equally, to achieve what Tech A says, a special tool can be used for comparing the position of camshaft sensor to crankshaft sensor. Therefore, both technicians are correct.

6 0

3 years ago

A 1,250 W electric motor is connected to a 220 Vrms, 60 Hz source. The power factor is lagging by 0.65. To correct the pf to 0.9

Black_prince [1.1K]

Answer:

$C = 46.891 \mu F$

Explanation:

Given data:

v = 220 rms

power factor = 0.65

P = 1250 W

New power factor is 0.9 lag

we knwo that

$s = \frac{P}{P.F} < COS^{-1} 0.65$

$S = \frac{1250}{0.65} < 49.45$

s = 1923.09 < 49.65^o

s = [1250 + 1461 j] vA

$P.F new = cos [tan^{-1} \frac{Q_{new}}{P}]$

solving for $Q_{new}$

$Q_{new} = P tan [cos^{-1} P.F new]$

$Q_{new} = 1250 [tan[cos^{-1}0.9]]$

$Q_{new} = 605.40 VARS$

$Q_C = Q - Q_{new}$

$Q_C = 1461 - 605.4 = 855.6 vars$

$Q_C = \frac[v_{rms}^2}{xc} =v_{rms}^2 \omega C$

$C = \frac{Q_C}{ v_{rms}^2 \omega}$

$C = \frac{855.6}{220^2 \times 2\pi \times 60}$

$C = 4..689 \times 10^{-5}$ Faraday

$C = 46.891 \mu F$

6 0

4 years ago

Sasha sits on a horse on a carousel 3.5 m from the center of the circle. She makes a revolution once every 8.2 seconds. What is

Leokris [45]

Answer: 2.7 m/s

Explanation:

Given the following :

Period (T) = 8.2 seconds

Radius = 3.5 m

The tangential speed is given as:

V = Radius × ω

ω = angular speed = (2 × pi) / T

ω = (2 × 22/7) / 8.2

ω = 6.2857142 / 8.2

ω = 0.7665505

Therefore, tangential speed (V) equals;

r × ω

3.5 × 0.7665505 = 2.6829268 m/s

2.7 m/s

6 0

4 years ago

During the sudden impact of a car accident, a person's neck can experience abnormal forces, resulting in an injury commonly know

iVinArrow [24]

Answer:

C) Rear

Explanation:

For better understanding, let me explain first what actually is the Whiplash injury. It usually occurs in the accidents related to vehicles and cause injury in the neck. It happens because of the very forceful, rapid movement of head and neck forward and backward. So unfortunately if there is a sudden impact of car from the rear and if it's velocity changes from 10 to 15 km/h (as the studies show) it will results in the whiplash injuries. So the correct option here is the third one "<em>rear</em>".

8 0

3 years ago

Which substance is uniquely a product of incomplete combustion of a fossil fuel?

Serga [27]

I can think of two of them:

-- carbon monoxide

-- black soot

3 0

4 years ago