Answer:
Explanation:
Given ,
dv / dt = k ( 160 - v )
dv / ( 160 - v ) = kdt
ln ( 160 - v ) = kt + c , where c is a constant
when t = 0 , v = 0
Putting the values , we have
c = ln 160
ln ( 160 - v ) = kt + ln 160
ln ( 160 - v / 160 ) = kt
(160 - v ) / 160 = 
1 - v / 160 = 
v / 160 = 1 - 
v = 160 ( 1 -
)
differentiating ,
dv / dt = - 160k 
acceleration a = - 160k 
given when t = 0 , a = 280
280 = - 160 k
k = - 175
a = - 160 x - 175 
a = 28000 
when a = 128 t = ?
128 = 28000 
= .00457
The distance from a 27 mw point source of electromagnetic waves where the electric field amplitude 0. 060 v/m will be 21.21 m .
Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.
The highest point of a wave is known as 'crest' , whereas the lowest point is known as 'trough'. Electromagnetic waves can be split into a range of frequencies. This is known as the electromagnetic spectrum.
c = 3 *
m/s
∈ = 8.85 *
/ N/ 
E = 0. 060 v/m
I = P / 4π
Also , I = c ∈
/2
= P / 4π I equation 1
substituting the value of I in equation 1
= 2 P / 4π (c ∈
)
= 2 * 27 *
/ 4 * 3.14 * 3 *
* 8.85 *
* 
r = 21.21 m
To learn more about Electromagnetic waves here
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Answer:
-v/2
Explanation:
Given that:
- Collides with the wall going through a sliding motion on on the plane smooth surface.
- Upon rebounding from the wall its kinetic energy becomes one-fourth of the initial kinetic energy before collision.
<u>We know, kinetic energy is given as:</u>

consider this to be the initial kinetic energy of the body.
<u>Now after collision:</u>


Considering that the mass of the body remains constant before and after collision.

Therefore the velocity of the body after collision will become half of the initial velocity but its direction is also reversed which can be denoted by a negative sign.
To solve this problem it is necessary to apply the concepts related to heat exchange in the vegetable and water.
By definition the exchange of heat is given by

where,
m = mass
c = specific heat
= Change in temperature
Therefore the total heat exchange is given as


Our values are given as,
Total mass is
= 200lb ,however the mass of solid vegetable and water is given as,



Replacing at our equation we have,



Therefore the heat removed is 22411.2 Btu
Air sample of places around the world compared to clean air