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Can you explain the answer of this question below:
The length of the shadow of a rod inclined at 10o to the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod is
- A:[(2.05 sin38°)/(sin42°)]
- B:[(2.05 cos38°)/(sin42°)]
- C:[(2.05 sin42°)/(sin38°)]
- D:[(2.05 cos42°)/(sin38°)]
- E:undefined
The answer is a.
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Can you explain the answer of this question below:The length of the sh...
)/(sin80)] metres
b)[(2.05 sin80)/(sin38)] metres
c)[(2.05 cos38)/(cos80)] metres
d)[(2.05 cos80)/(cos38)] metres
We can use the following formula to solve the problem:
length of rod/length of shadow = tan(elevation angle)
where the elevation angle is the angle between the sun and the horizon.
Let L be the length of the rod. Then we have:
L/2.05 = tan(38)
L = 2.05 tan(38)
Now, we need to find the angle between the rod and the vertical, which is 90-10=80 degrees. We can use the sine formula to find the length of the shadow:
length of shadow/sin(80) = L/sin(80-10)
length of shadow = L*sin(80)/sin(70)
Substituting L = 2.05 tan(38), we get:
length of shadow = (2.05 tan(38) * sin(80))/sin(70)
Simplifying the expression, we get:
length of shadow = (2.05 sin(38)*sin(80))/cos(80)
Using the identity sin(80) = cos(10), we get:
length of shadow = (2.05 sin(38)*cos(10))/cos(80)
Finally, using the identity cos(80) = sin(10), we get:
length of shadow = (2.05 sin(38)*cos(10))/sin(10)
Multiplying both numerator and denominator by 2, we get:
length of shadow = (4.1 sin(38)*cos(10))/(2*sin(10))
Using the identity sin(2x) = 2sin(x)cos(x), we get:
length of shadow = (4.1 sin(38)*sin(80))/sin(20)
Using the identity sin(180-x) = sin(x), we get:
length of shadow = (4.1 sin(38)*sin(100))/sin(20)
Finally, using the identity sin(100) = sin(80), we get:
length of shadow = (4.1 sin(38)*sin(80))/sin(20)
Therefore, the answer is (a) [(2.05 sin(38))/(sin(80))] metres.
b)[(2.05 sin80)/(sin38)] metres
c)[(2.05 cos38)/(cos80)] metres
d)[(2.05 cos80)/(cos38)] metres
We can use the following formula to solve the problem:
length of rod/length of shadow = tan(elevation angle)
where the elevation angle is the angle between the sun and the horizon.
Let L be the length of the rod. Then we have:
L/2.05 = tan(38)
L = 2.05 tan(38)
Now, we need to find the angle between the rod and the vertical, which is 90-10=80 degrees. We can use the sine formula to find the length of the shadow:
length of shadow/sin(80) = L/sin(80-10)
length of shadow = L*sin(80)/sin(70)
Substituting L = 2.05 tan(38), we get:
length of shadow = (2.05 tan(38) * sin(80))/sin(70)
Simplifying the expression, we get:
length of shadow = (2.05 sin(38)*sin(80))/cos(80)
Using the identity sin(80) = cos(10), we get:
length of shadow = (2.05 sin(38)*cos(10))/cos(80)
Finally, using the identity cos(80) = sin(10), we get:
length of shadow = (2.05 sin(38)*cos(10))/sin(10)
Multiplying both numerator and denominator by 2, we get:
length of shadow = (4.1 sin(38)*cos(10))/(2*sin(10))
Using the identity sin(2x) = 2sin(x)cos(x), we get:
length of shadow = (4.1 sin(38)*sin(80))/sin(20)
Using the identity sin(180-x) = sin(x), we get:
length of shadow = (4.1 sin(38)*sin(100))/sin(20)
Finally, using the identity sin(100) = sin(80), we get:
length of shadow = (4.1 sin(38)*sin(80))/sin(20)
Therefore, the answer is (a) [(2.05 sin(38))/(sin(80))] metres.
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Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a.
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Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a..
Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a..
Solutions for Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. in English & in Hindi are available as part of our courses for JEE.
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Here you can find the meaning of Can you explain the answer of this question below:The length of the shadow of a rod inclined at 10oto the vertical towards the sun is 2.05 metres when the elevation of the sun is 38o.The length of the rod isA:[(2.05 sin38°)/(sin42°)]B:[(2.05 cos38°)/(sin42°)]C:[(2.05 sin42°)/(sin38°)]D:[(2.05 cos42°)/(sin38°)]E:undefinedThe answer is a. defined & explained in the simplest way possible. Besides giving the explanation of
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