Which of the following is NOT a vector quantity? (A) Acceleration
(B) Average velocity
(C) Linear momentum
(D) Potential energy
(E) Force

D

Explanation:

Acceleration has both magnitude and direction. because velocity is vector quantity

average velocity is vector

linear momentum = mass× velocity

therefore it's also vector

force = mass× acceleration

acceleration is vector therefore force also vector

potential energy= mgh

energy in any form is scaler quantity therefore potential energy too is a scaler quantity.

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

the answer is a. hope this .