Active and Passive Remote Sensing

Q. Assertion (A): Any device in which the sensor does not use its own source of energy can be called a passive remote sensing device.
Reason (R): Passive remote sensing device can function properly without any dependence on external weather.
Select the correct statement.

1. Both A and R are true, and R is the correct explanation of A.
2. Both A and R are true, but R is not the correct explanation of A.
3. A is true, but R is false.
4. A is false, but R is true.

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Which type of sensor emits energy waves of its own to detect objects?

1. Humidity Sensors
2. Particle Sensors
3. Radar Sensors
4. Radiation Sensors