(a) 60°
(b) 75"
(iv) Now the jib BR, has been rotated and the length RS is increased. The load is now on the ground at a point 8 m
(C) 30
from A. What is the angle through which the jib has been rotated?
(a) 15°
(b) 25°
hu which RS has been increased?
(c) 30°
(d) 45°
Answers
Given : Crane stands on a level ground.
It is represented by a tower AB, of height 11 m
jib is of length 16 m and can rotate in a vertical plane about B
A vertical cable, RS , carries a load S
The diagram shows current position of the jib, cable and load
BR = 16 , RS = 8
To Find : length BS
(a) 8√ 3 m
(b) 4√ 3 m
(c) 4√ 2 m
(d) 8√ 2 m
Solution:
BR = 16
RS = 8
Applying Pythagorean theorem :
BS² =BR² - RS²
=> BS² = 16² - 8²
=> BS² = 8²( 2² - 1)
=> BS² = 8²(4 - 1)
=> BS² = 8²(3)
=> BS = 8√3
length BS = 8√3 m
angle that the jib, BR, makes with the horizontal
Sin θ = 8/16
=> Sin θ =1/2
=> θ = 30°
∠BRS = 90° - 30° = 60°
Learn More:
If diagonal of a rectangle is 26 cm and one side is 24 cm, find the ...
brainly.in/question/4732852
The distance between Q and R=100 km
brainly.in/question/13455320
Answer:
Now the jib BR, has been rotated and the length RS
is increased. The load is now on the ground at a point
8 m from A. What is the angle through which the jib
has been rotated ?