J J Science Academy - Physics Questions

Question 1: An uniformly accelerated body travels a distance of 24 m in $ 5^{\\text {th }} $ second of its motion and 44 m in $ 15^{\\text {th }} $ sec of its motion. The acceleration of the particle will be

1) $ 1 m / s^{2} $2) $ 2 m / s^{2} $3) $ 4 m / s^{2} $4) $ 0.5 m / s^{2} $

Hint: $$ s_n = u + \frac{1}{2} g(2n-1) $$$$ 24 = u + \frac{9 a}{2} $$ $ \ldots $ (i)$$ 44 = u + \frac{29 a}{2} $$ (ii)(ii) - (i) gives$$ 20 = 10a $$$$ a = 2 m / s^{2} $$

Question 2: A body, starting with some velocity, experiences uniform acceleration. It travels a distance of 20 m in $ 5^{\\text {th }} $ second and 36 m in $ 9^{\\text {th }} $ second. The acceleration of the particle (in $ m / s^{2} $ ) is

1) 42) 23) 64) 8

Hint: $$ s_n = u + \frac{1}{2} g(2n-1) $$$$ 20 = u + \frac{9 a}{2} $$ $ \ldots $ (i)36 = u + 17a (ii)(ii) - (i) gives 16=4a a = 4 m/s2

Question 3: A particle starts moving along a straight line with velocity ' $ u $ ' and a constant acceleration ' $ a $ ', the initial velocity is

1) $ 1 m / s $2) $ -1 m / s $3) $ 2 m / s $4) $ -2 m / s $

Hint: $$ s_9 = u + \frac{1}{2}(4)[2(9)-1] $$$$ 36 = u+34 $$$$ u = 2 m / s $$

Question 4: A particle starts moving along a straight line with velocity ' $ u $ ' and a constant acceleration ' $ a $ ', the distance it travels in $ 15^{\\text {th }} $ second is

1) 54 m2) 58 m3) 60 m4) 64 m

Hint: $$ s_n = u + \frac{1}{2} g(2 n-1) = 2 + \left[\frac{1}{2} \times 4 \times 29\right] = 2+58=60 m $$