Q1.A car travels a distance 100 m with a constant
acceleration and average velocity of 20 m s-l. The
final velocity acquired by the car is 25 m s-1.
Find : (i) the initial velocity and (ii) acceleration
Answers
Explanation:
EXPLANATION.
GIVEN
A car travel a distance 100 m with a constant
acceleration and average velocity of 20 m/s
The final velocity acquired by the car = 25 m/s
To find.
1) = The initial velocity.
2) = Acceleration of a car.
=> 20 = 100 / T
=> T = 5 seconds.
average velocity= u+v/2
=> 20 = u + 25 / 2
=> 40 = u + 25
=> 15 = u
From Newton first equation of
kinematics.
=> v = u + at
=>
25 = 15 + 5a
=> 10 = 5a
=> a = 2 m/s²
Therefore,
1) = initial velocity = 15 m/s
2) = acceleration = 2 m/s²
__thanks__
Explanation:
To solve this question easily, one needs to remember the direct result of finding image position based on object position.
According to that,
If object is at infinity, then image is formed at F.
If object is beyond C, image is formed between F & C.
If object is at C, then image is also at C.
If object is between F & C, then image is beyond C.
If object is at F, image is formed at infinity.
If object is between P & F, then image is formed behind the mirror.
The first 5 cases refer to the formation of a real image. The 6th case shows the formation of a virtual image.
According to the question, magnification is equal to -1. Here negative sign implies, image is real and inverted while value of 1 implies object and image are of the same size. Real image is formed only by a concave mirror. Hence the type of mirror used is Concave.
By the above cases, we get to know that the image and object have the same distance only if they both are placed at the center of curvature (C).
Hence the distance between object and image is zero units. (v-u = 0cm)