21)From a helicopter a person observes an object on the ground at an angle of depression 30°. If the helicopter is flying at a height of 500 m from the ground, then the distance between the person and the object is
ఒక హెలికాప్టర్ నుండి ఒక వ్యక్తి భూమి పైనున్న ఒక వస్తువును 30° నిమ్నకోణంలో పరిశీలించాడు. భూమి పై నుండి హెలికాప్టర్ 500 మీ. ఎత్తులో ఎగురుతూ ఉంటే, వ్యక్తికి మరియు వస్తువుకు మధ్య దూరము
A) 500 m
B) 1000 m
C)
D)
View Answer
B) 1000 m
Explanation:🎯 Shortcut Method Using Trigonometry (Hypotenuse Calculation)
We are given:
– The angle of depression from the helicopter to the object on the ground is .
– The height of the helicopter from the ground is 500 meters.
We need to find the distance between the person and the object (which is the hypotenuse of the right triangle formed by the height, the distance on the ground, and the line of sight).
Step 1: Using the Angle of Depression and Trigonometric Ratio
In this case, the angle of depression forms a right triangle with:
– The height of the helicopter as the opposite side (500 m),
– The distance between the person and the object as the hypotenuse,
– The horizontal distance between the object and the point on the ground directly beneath the helicopter as the adjacent side.
We can use the tangent function to relate the height and the horizontal distance first, then apply the cosine or sine to find the hypotenuse.
Since , we have:
Solving for the horizontal distance:
Step 2: Apply the Pythagorean Theorem
Now, we can calculate the distance between the person and the object (the hypotenuse). We know:
– The height (opposite side) is 500 m,
– The horizontal distance (adjacent side) is .
Using the Pythagorean theorem:
Final Answer:
22)The product of prime factors of 2024 is
2024 యొక్క ప్రధాన కారణాంకాల లబ్ధము
A) 11 × 23 × 32
B) 23 × 11 × 23
C) 7 × 23 × 23
D) 23 × 112 × 22
View Answer
B) 23 × 11 × 23
Explanation:🎯 Shortcut Method to Find the Prime Factorization of 2024
We need to find the prime factorization of 2024.
Step 1: Start by dividing 2024 by the smallest prime (2):
Now, 253 is not divisible by 2, so we move to the next smallest prime, which is 3. However, 253 is not divisible by 3 either, so we check for divisibility by 5, and it’s not divisible by 5 either.
Step 2: Check divisibility by 11:
23 is a prime number, so the prime factorization of 2024 is:
Final Answer:
23){0} is a set which has ______ elements.
{0} అనేది ______ మూలకాలను కలిగి ఉన్న సమితి.
A) 0
B) 1
C) 4
D) 3
View Answer
B) 1
Explanation:🎯 Explanation:
The set is a set containing a single element, which is .
So, the number of elements in the set is 1.
Final Answer:
24)If cosec θ + cot θ = k, then the value of cosec θ is
cos ec θ + cot θ = k అయిన, cosec θ యొక్క విలువ
A)
B) 0
C)
D)
View Answer
A)
Explanation:🎯 Shortcut Method to Find in Terms of
We are given that:
We need to express in terms of .
Step 1: Use the identity for
We know that:
Rearranging the given equation:
Now, we square both sides of this equation:
Expanding the square:
Using the identity , we substitute:
Step 2: Simplify the equation
Canceling out from both sides:
Rearranging:
Final Answer:
25)The value of is యొక్క విలువ
A) 0
B) 1
C) 2
D) 3
View Answer
B) 1
Explanation:🎯 Shortcut Method to Simplify the Expression
We are asked to simplify the expression:
Step 1: Apply the logarithmic property of addition
We use the property of logarithms that states:
So, applying this property:
Step 2: Simplify
We know that:
So:
Final Answer:
26)Which of the following two sets are equal sets?
క్రింది రెండు సమితులలో ఏవి సమాన సమితులు?
A) A = {5, 6}, B = {5}
B) A = {5, 6}, B = {5, 6, 7}
C) A = {5, 6, 7}, B = {7, 5, 6}
D) A = {5, 6, 8}, B = {5, 6, 7}
View Answer
C) A = {5, 6, 7}, B = {7, 5, 6}
Explanation:🎯 Understanding Equal Sets
Two sets are equal sets if and only if they have exactly the same elements. The order of the elements in a set does not matter.
Step-by-step analysis of each option:
– 1. A = {5, 6}, B = {5}
– Set A has the elements 5 and 6.
– Set B has only the element 5.
– These are not equal sets, because Set A has an additional element (6) that Set B does not have.
– 2. A = {5, 6}, B = {5, 6, 7}
– Set A has the elements 5 and 6.
– Set B has the elements 5, 6, and 7.
– These are not equal sets, because Set B has an extra element (7) that Set A does not have.
– 3. A = {5, 6, 7}, B = {7, 5, 6}
– Set A has the elements 5, 6, and 7.
– Set B has the same elements, 5, 6, and 7, but in a different order.
– These are equal sets, because they contain exactly the same elements, just in a different order. The order does not matter in sets.
4. A = {5, 6, 8}, B = {5, 6, 7}
– Set A has the elements 5, 6, and 8.
– Set B has the elements 5, 6, and 7.
– These are not equal sets, because Set A contains 8, while Set B contains 7. They have different elements.
Final Answer:
27)Exponential form of యొక్క ఘాత రూపము
A) ba=c
B) ac=b
C) ab=c
D) bc=a
View Answer
D) bc=a
Explanation:🎯 Understanding the Exponential Form of Logarithms
The logarithmic equation means that the exponent to which the base must be raised to produce is .
This can be rewritten in exponential form as:
Explanation:
– implies that raised to the power gives .
– So, in exponential form, we have:
Final Answer:
28)If a right circular cylinder has base radius 14 cm and height 21 cm, then its curved surface area is ______.
ఒక క్రమ వృత్తాకార స్థూపము యొక్క భూవ్యాసార్ధము 14 సెం. మీ. మరియు ఎత్తు 21 సెం.మీ. అయిన, ఆ స్థూపము వక్రతల వైశాల్యము _____.
A) 924 cm2
B) 2772 cm2
C) 3080 cm2
D) 1848 cm2
View Answer
D) 1848 cm2
Explanation:🎯 Shortcut Method to Find the Curved Surface Area of a Cylinder
The formula for the curved surface area (CSA) of a right circular cylinder is:
Where:
– = radius of the base
– = height of the cylinder
–
Given:
– Radius
– Height
–
Step 1: Substitute the values into the formula
Step 2: Simplify the calculation
Final Answer:
29)The volume of a right circular cone with radius 6 cm and height 7 cm is ________.
6 సెం.మీ. భూవ్యాసార్ధము మరియు 7 సెం.మీ. ఎత్తు కలిగిన ఒక క్రమ వృత్తాకార శంఖువు యొక్క
A) 264 cm3
B) 792 cm3
C) 301 cm3
D) 616 cm3
View Answer
A) 264 cm3
Explanation:🎯 Shortcut Method to Find the Volume of a Right Circular Cone
The formula for the volume of a right circular cone is:
Where:
– = radius of the base
– = height of the cone
–
Given:
– Radius
– Height
–
Step 1: Substitute the values into the formula
Step 2: Simplify the calculation
Cancel the 7’s:
Now, multiply:
Final Answer:
30)The value of is యొక్క విలువ
A) 0
B) 1
C)
D)
View Answer
B) 1
Explanation:🎯 Simplifying the Expression
We are asked to find the value of:
Step 1: Use the Pythagorean identity
The Pythagorean identity states that:
This identity holds for any angle , including .
Step 2: Apply the identity to the given expression
Final Answer:
This is the simplest and quickest method, using the basic trigonometric identity.