Answer:
Your answer would be C, Radio waves.
Explanation:
Answer:
The focal length of the mirror is 52.5 cm.
Explanation:
Given that,
Object to Image distance d = 140 cm
Image distance v= 35 cm
We need to calculate the object distance


We need to calculate the focal length
Using formula of mirror

Put the value into the formula



Hence, The focal length of the mirror is 52.5 cm.
Answer:
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive
Explanation:
let 'd' be distance b/w Los Angeles and San Francisco i.e 400 mi
considering ,
Alan's speed
=50mph
Beth's speed
=60mph
->For Alan:
The time required
= d/
= 400/50 => 8h
-> For beth:
The time required
=> 6h 40m
Alan will reach at 8:00 a.m +8h = 4:00p.m.
Beth will reach at 9:00 a.m +6h 40m= 3:40p.m.
a) Beth will reach before Alan
b)Beth has to wait 20 min for Alan to arrive