A man in a boat rowing away from lighthouse 200 m high takes 2 minutes to change the angle of elevation of the top of the lighthouse from 60° to 45º. Find the speed of boat.
Answers
Answered by
1
Answer:
Step-by-step explanation:
Consider ΔABC
Where AB is Height of Tower
BC is distance from boat to tower
tanC=
BC
AB
⟹
3
=
BC
100
⟹BC=57.73
Now let D be the point the boat travelled
tanD=
BD
AB
⟹
3
1
=
BD
100
⟹BD=173.2
Distance travelled by boat CD=BD−BC=173.2−57.73=115.47m
Speed of boat=
2
115.47
=57.73m/min
Similar questions