Question

Plz. Tell these answers ​

Answer 1

Answer:

1)The area under a speed-time graph represents the distance travelled. This is a velocity time graph of an object moving in a straight line due North. ... A horizontal line on a speed-time graph represents a constant speed. A sloping line on a speed-time graph represents an acceleration.

2)(1) First equation of Motion:

V = u + at

soln.

Consider a body of mass “m” having initial velocity “u”.Let after time “t” its final velocity becomes “v” due to uniform acceleration “a”.

Now we know that:

Acceleration = change in velocity/Time taken

=> Acceleration = Final velocity-Initial velocity / time taken

=> a = v-u /t

=>at = v-u

or v = u + at

This is the first equation of motion.

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(2) Second equation of motion:

s = ut + 1/2 at^2

sol.

Let the distance travelled by the body be “s”.

We know that

Distance = Average velocity X Time

Also, Average velocity = (u+v)/2

.: Distance (t) = (u+v)/2 X t …….eq.(1)

Again we know that:

v = u + at

substituting this value of “v” in eq.(2), we get

s = (u+u+at)/2 x t

=>s = (2u+at)/2 X t

=>s = (2ut+at^2)/2

=>s = 2ut/2 + at^2/2

or s = ut +1/2 at^2

This is the 2nd equation of motion.

……………………………………………………………

(3) Third equation of Motion

v^2 = u^2 +2as

sol.

We know that

V = u + at

=> v-u = at

or t = (v-u)/a ………..eq.(3)

Also we know that

Distance = average velocity X Time

.: s = [(v+u)/2] X [(v-u)/a]

=> s = (v^2 – u^2)/2a

=>2as = v^2 – u^2

or v^2 = u^2 + 2as

This is the third equation of motion.

(3)Retardation is nothing but a negative acceleration. The velocity of the body may either increase or decrease. The change in velocity is known as acceleration. ... Retardation is acceleration with a negative sign. Or the negative value of acceleration shows that the velocity of a body is decreasing.

(4)Average speed is calculated by dividing the total distance that something has traveled by the total amount of time it took it to travel that distance. Speed is how fast something is going at a particular moment. Average speed measures the average rate of speed over the extent of a trip.

(5)= 0.000 077 160 4938 m/s2

(6)initial velocity= 10m/s

final velocity= 40m/s

time taken= 3sec

acceleration=( final velocity - initial velocity)/time taken

= (40-10)/3  

= 30/3

=10m/s^2

(7) when the object doesnt change position with time it is said to be in rest

(8)yes

(10) SI unit of velocity = meter/second or m/s or ms^-1  

PLEASE MARK AS THE BRAINLIEST ,,,,, TOOK A LOT OF TIME:)