Question : Which of the following is the correct statement?

Option 1: Joule is the unit of work

Option 2: The unit of energy is the watt.

Option 3: Joule/ second is also a unit of energy.

Option 4: The unit of power is joule/newton.

Question : Find the value of $\left(\tan ^2 \theta+\tan ^4 \theta\right)$.

Option 1: $\cot ^2 \theta-\tan ^2 \theta$

Option 2: $\ {\sec}^4 \theta-\ {\sec}^2 \theta$

Option 3: $\ {\sec}^4 \theta-\ {\sec}^4 \theta$

Option 4: $ \ {\sec}^4 \theta+\ {\sec}^2 \theta$

Question : The SI (International System of Units) unit of length is______.

Option 1: metre

Option 2: centimetre

Option 3: millimetre

Option 4: kilometre

Question : Which of the following is the unit of perceived loudness of sound?

Option 1: Decibel

Option 2: Sone

Option 3: Hertz

Option 4: Phon

Question : The angle of elevation of an aeroplane from a point on the ground is 60°. After 15 seconds of flight, the elevation changes to 30°. If the aeroplane is flying at a height of $1500\sqrt{3}$ metre, find the speed of the plane:

Option 1: 300 m/sec

Option 2: 200 m/sec

Option 3: 100 m/sec

Option 4: 150 m/sec