Ans 1:- The following points explain the differences between distance and displacement:-

✒The amount of space between two points, measured along the actual path, which connects the two points, is called distance. The amount of space between two points, measured along the minimum path which connects them, is called displacement.

✒Distance is nothing but the length of the total route travelled by the object during motion. On the other hand, displacement is the least distance between starting and finishing point.

✒Distance gives the complete information of the path followed by the body. As against this, displacement does not give the complete information of the path travelled by the object.

✒Displacement decreases with time, whereas distance does not decrease with time.

✒The value of displacement can be positive, negative or even zero, but the value of the distance is always positive.

✒Distance is a scalar measure, which takes into account the magnitude only, i.e. we need to specify only the numerical value. Unlike displacement which is a vector measure and takes into account both magnitude and direction.

✒Distance covered is not the unique path, but the displacement between two locations, is the unique path.

While distance is represented by ‘d’, displacement is labelled as ‘s’.

✒Distance can be calculated by multiplying speed and time. On the contrary, the displacement can be calculated by multiplying velocity and time.

Ans 2:- u = 20m/s ; s = 50m and v = 0m/s

Using, V^2 = u^2 + 2as

a = (v^2 – u^2)/2s

a = (0^2 - 20^2)/(2 x 50) = - 4m/s^2

Acceleration = -4 m/s2 or, retardation = 4 m/s2

Ans 3:- Speed is how fast an object is moving. It is calculated by the displacement of space per a unit of time. Velocity is the rate at which an object changes position in a certain direction. It is calculated by the displacement of space per a unit of time in a certain direction. Velocity deals with direction, while speed does not.

Ans 4:-

OSMOSIS Vs DIFFUSION

Osmosis:- The movement of liquid (solvent) especially water from the higher region concentration to the region of lower concentration, through the semipermeable membrane is called osmosis.

VS.

Diffusion:- The movement of molecules (solid, liquid or gases) from a region of higher concentration to the lower region concentration, but not necessarily through a semi-permeable membrane is called diffusion.

Osmosis:-Semi-permeable membrane The motion is through the semi-permeable membrane.

VS.

Diffusion:-The motion is direct and does not require the semi-permeable membrane.

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