Question

What is the sound level in a car when the intensity is 0.5 pW/m2?

Answer 1

Level of sound is given by equation

$L = 10 Log \frac{I}{I_0}$

here we know that

$I = 0.5 pW/m^2$

also the standard intensity of sound will be

$I_0 = 1 pW/m^2$

now we will use above equation

$L = 10 Log\frac{0.5}{1}$

$L = -3.0 dB$

So here it is no given option is correct as its level is coming - 3 dB

Answer 2

Answer: 1. C) 57 dB

2. A) 5.5 x 10^ -15 J

3. D) 1.4 m

4. D) 47 cm

5. A) 6.2 MHz

6. B) -18.2 dB

7. A) 2.8 uJ

8. C) 90 m

9. C) 511 W

10. C) 3.16 x 10^ -7 W/m^2

Explanation: 100% for quick check :)