All categories

3 years ago

1. When an object's distance from another object is changing it must be

1 answer:

3 0

An object is in motion if its distance from another object is changing. An object is in motion if it changes position relative to a reference point. An reference point is a place or object used for comparison to determine if something is moving.

You might be interested in

PLEASE HELP ME I DONT UNDERSTAND THIS

lukranit [14]

Answer:

A) compression B) rarefaction C) wavelength

Explanation:

6 0

2 years ago

A laborer pushes a box to distance of 20m. if the force required to push the box is 25N what will be the quantity of work done

Marrrta [24]

Answer:

500 J

Explanation:

In the case of a rectilinear movement, the work is calculated as the product of Force (N) * movement (m). In your case, unless the angle between the force vector and the displacement vector is different from 0, the work is:

25 N * 20 m = 500 J

7 0

2 years ago

An ac generator with peak voltage 100 volts is placed across a 10-? resistor. What is the average power dissipated?

Romashka [77]

The correct answer is: Average Power = 500 W

Explanation:
Root-mean square voltage = Vrms = Vpeak /√2 = 100 / √2 volts
Resistance = R = 10 Ω
Average power = Pavg = (Vrms)^2<span> / R </span>= (100 * 100) / (2 * 10) = <span>500 W</span>

3 0

3 years ago

Unless indicated otherwise, assume the speed of sound in air to be v = 344 m/s. A stationary police car emits a sound of frequen

bixtya [17]

Answer:

a) The velocity of the car is 7.02 m/s and the car is approaching to the police car as the frequency of the police car is increasing.

b) The frequency is 1404.08 Hz

Explanation:

If the police car is a stationary source, the frequency is:

$f_{a} =(\frac{v+v_{c} }{v} )f_{s}$ (eq. 1)

fs = frequency of police car = 1200 Hz

fa = frequency of moving car as listener

v = speed of sound of air

vc = speed of moving car

If the police car is a stationary observer, the frequency is:

$f_{L} =f_{a} (\frac{v}{v-v_{c} } )=(\frac{v+v_{c} }{v-v_{c} } )f_{s}$ (eq. 2)

Now,

fL = frequecy police car receives

fs = frequency police car as observer

a) The velocity of car is from eq. 2:

$1250=1200(\frac{v+v_{c} }{v-v_{c} } )\\1250(v-v_{c} )=1200(v+v_{c} )\\v_{c} =\frac{50*344}{2450} =7.02m/s$

b) Substitute eq. 1 in eq. 2:

$f_{L} =(\frac{v+v_{p} }{v-v_{c} } )(\frac{v+v_{c} }{v-v_{p} } )f_{s} =(\frac{344+20}{344-7.02} )(\frac{344+7.02}{344-20} )*1200=1404.08Hz$

7 0

3 years ago

Give examples of plants that can reproduce by vegetative reproduction.

marishachu [46]

Answer:

Some examples of vegetative propagation are farmers creating repeated crops of apples, corn, mangoes or avocados through asexual plant reproduction rather than planting seeds. Vegetative propagation can be accomplished from side-shoots, slips, stems and sections of tubers, bulbs or rhizomes.

Explanation:

5 0

3 years ago