Question

the second hand of a clock makes five and half turn find the number of right angle that is turn ​

Answer 1

Answer:

Given:

△ABC is right angled at C, ∠B=60

∘

∠C=90

∘

We know that,

In triangle ABC, ∠A+∠B+∠C=180

∘

60

∘

+∠A+90

∘

=180

∘

∠A=30

∘

We have,

sinA=

AB

CB

sin30

∘

=

15

CB

2

1

×15=CB

CB=7.5 units

From Pythagoras theorem,

AB

2

=AC

2

+BC

2

15

2

=AC

2

+(

2

15

)

2

AC

2

=225−(

4

225

)

AC

2

=225(

4

3

)

AC=

2

15

3

units