Assertion (A): Gamma rays are fundamentally un-deflected by electric and magnetic fields. Reason (R): Gamma rays carry no electrical charge. MCQ with Answer and Explanation
Assertion (A): Gamma rays are fundamentally un-deflected by electric and magnetic fields. Reason (R): Gamma rays carry no electrical charge.
A. A is false but R is true.
B. A is true but R is false.
C. Both A and R are true but R is NOT the correct explanation of A.
D. Both A and R are true and R is the correct explanation of A.
Answer: Option D
Solution (By JKExamLibrary)
Electric fields deflect charged particles via Coulomb forces (F=qE), and magnetic fields deflect moving charged particles via Lorentz forces (F=qvB). Gamma rays are purely high-energy electromagnetic photons. Because they lack any electrical charge (q=0), both electric and magnetic forces on them are exactly zero. Therefore, they pass through fields completely un-deflected. R explains A perfectly.
Explanation:
To convert a temperature from Celsius to Kelvin, the formula is K = °C + 273.15. For most physics problems, we use 273. Therefore, K = 25 + 273 = 298 K. Kelvin is the SI unit of temperature, and it never uses a degree symbol.
Explanation:
SONAR (Sound Navigation and Ranging) relies on the reflection of ultrasonic waves. A transmitter sends out sound waves, which travel through water, strike an object (like a submarine or the seabed), and reflect back as an echo to a receiver. By measuring the time taken for the echo to return, the distance can be calculated.
Explanation:
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