Physics 1st Paper MCQ-Chittagong Board-2019

1. When a particle oscillates with a simple harmonic notions?

[All the symbols have their usual meanings]

i. Potential energy $E_{p}=\frac{1}{2} \mathrm{kA}^{2} \sin ^{2}(\omega t+\delta)$

ii. Kinetic energy $E_{k}=\frac{1}{2} k A^{2} \cos ^{2}(\omega t+\delta)$

iii. Total energy $E \propto A^{2}$

Which one of the following is correct?

2. Read the following stem and answer the question nos. 6 and 7 :

A body is thrown with an angle of $30^{\circ}$ and velocity of $50 \mathrm{~ms}^{-1}$ from the ground.

What is the velocity of the body after 2 second?

3. What is the dimension of velocity?

4. What will be the spring constant when $5 N$ force expands the spring to $10 \mathrm{~cm}$ ?

5. What is the angle between a vector and its unit vector?