You need to observe the car at two different times.
-- The first time:
You write down the car's speed, and the direction it's pointing.
-- The second time:
You write down the car's speed and the direction it's pointing, again.
You take the data back to your lab to analyze it.
-- You compare the first and second speed. If they're different,
then the car had acceleration during the time between the two
observations.
-- You compare the first and second direction. If those are different,
even if the speeds are the same, then the car had acceleration during
the time between the two observations.
(Remember, "acceleration" doesn't mean "speeding up".
It means any change in speed or direction of motion.)
Answer:

Explanation:
given.
magnification(m) = 400 x
focal length (f_0)= 0.6 cm
distance between eyepiece and lens (L)= 16 cm
Near point (N) = 25 cm
focal length of the eyepiece (f_e)= ?
using equation





A.The swimmer pushes the water
C. the walls force against the ball
Answer:
c) may also be conserved
Explanation:
Momentum is conserved in both elastic and inelastic type of collisions.
But the differences is that:
In an ELASTIC type of collisions, KINETIC ENERGY IS ALSO CONSERVED.
whereas, In an INELASTIC type of collision, KINETIC ENERGY IS NOT CONSERVED.
So unless until type of collision is specified, we can not say anything about the conservation of kinetic energy after collision.
Hence, may also be conserved is the appropriate option here.
Answer:
Position =
behind the mirror
Nature = Virtual and Erect
Size =
: Diminished
Explanation:
Sign convention-Distance measured to the left of pole is negative and to the right of pole is positive.
Object distance = u = -20 cm
Focal length = f = Radius of curvature/2 = 30/2 = 15 cm
We have to use mirror formula to find image distance.

Since the image distance is positive, it is formed behind the mirror or a virtual image is formed.
Magnification = 

Height of the object = 5 cm
Height of the image = 
Since the height of the image is positive and less than the size of object,it is erect and diminished.