Question
A boat is being rowed away from a cliff 270 m high. From
the top of the cliff, the angle of depression of the boat changes from 60° to 45° in 2 minutes. What is the speed of the boat?Solution
According to the figure above: tan 45° = 270/(a + b) ⇒ 1 = 270/(a + b) ⇒ a + b = 270 Also, tan 60° = 270/a ⇒ √ 3 = 270/a ⇒ a = 270/ √ 3 ⇒ a = 90√ 3 = 155.8 ∴ b = 270 - 155.8 = 114.2 ⇒ The boat covers a distance of 114.2 m in 2 minutes. ∴ Speed of the boat = (114.2 x 60)/(2 x 1000) km/h = 3.4 km/h
Add suitable question tags to the following statements from among the choices given below them.
 You’ll be coming early tomorrow, _______?
Given below is a sentence with one blank in each. Below each sentence are given four words among which one word might fill the blank. If none of the w...
Fill in the blank with the most appropriate word.
They ….for 10 hours a day in summer and a mere seven in winter.
In the question given below, there is a sentence of which some parts have been jumbled. Rearrange these parts, which are labeled as P, Q, R, and S, to...
Turning around a __________ ship is never easy.
(A) large
(B) small
(C) tiny   Â
(D) huge   Â
Any disturbance, such as a ÂÂÂÂÂÂ___________ of stellar formation events that are sometimes found drawn out in a near-linear pattern, will eventua...
Fill in the blank with the correct option. I _Â in Hyderabad.
We have failed in our educational system to ……….. the enormous ………… talent in our country and ……… a solid foundation of science.
In the following questions, a sentence is given with two blanks. Identify the correct pair of words that fit in the sentence to make it grammatically a...
Directions: In each of the following sentences, a blank is given. Choose the most appropriate option from the provided choices to fill in the blank and...