# Question: 3 a 14kw radio transmitter is coupled to an antenna...

###### Question details

3. A 1.4-kW radio transmitter is coupled to an antenna by a cable whose attenuation is 1.8 dB. How much power reaches the antenna?

**4. **

**(a) **A newspaper is held 6 m from a 2000-cd street lamp at midnight. What is the maximum illumination of the newspaper?

(b) Find the solid angle subtended at the center of a sphere of radius 3.0 m by an area of 100 cm2 on its surface.

**Q5:** **)**

(a) A match **5 cm** long is placed **20 cm** in front of a concave mirror whose focal length is **50 cm**. Find the location, size, and nature of the image.

**(b)** A double convex lens has surfaces whose radii are **40 cm** and **50 cm**. The index of refraction of the glass is **1.52**. Find the focal length of the lens.

6. A horizontal pipe 3.5 cm in radius is joined to a pipe 14 cm in radius.

(a) If the velocity of seawater in the small pipe is 6 m/s and the pressure in there

is 8x10^5 Pa, find the velocity and pressure in the large pipe.

(b) What is the rate of flow through the pipe?