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Dot product of two vectors overset(rarr)...

Dot product of two vectors `overset(rarr)A` and `overset(rarr)B` is defined as `overset(rarr)A.overset(rarr)B=aB cos phi` , where `phi` is angle between them when they are drawn with tails coinciding. For any two vectors . This means `overset(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A` that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors `overset(rarr)A` and `overset(rarr)B` also called the cross product, is denoted by `overset(rarr)A xx overset(rarr)B` . As the name suggests, the vector product is itself a vector. `overset(rarr)C=overset(rarr)A xx overset(rarr)B` then `C=AB sin theta` ,
A force `overset(rarr)F=3hat i +c hat j + 2 hatk` acting on a particle causes a displacement `d=4hat i- 2 hat j + 3 hat k` . If the work done (dot product of force and displacement) is 6J then the value of c is :

A

12

B

0

C

6

D

1

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The correct Answer is:
To solve the problem, we need to find the value of \( c \) in the force vector \( \vec{F} = 3 \hat{i} + c \hat{j} + 2 \hat{k} \) given that the work done by this force during a displacement \( \vec{d} = 4 \hat{i} - 2 \hat{j} + 3 \hat{k} \) is 6 Joules. ### Step-by-step Solution: 1. **Write down the formula for work done:** The work done \( W \) by a force \( \vec{F} \) over a displacement \( \vec{d} \) is given by the dot product: \[ W = \vec{F} \cdot \vec{d} \] 2. **Substitute the given vectors into the work formula:** We have: \[ \vec{F} = 3 \hat{i} + c \hat{j} + 2 \hat{k} \] \[ \vec{d} = 4 \hat{i} - 2 \hat{j} + 3 \hat{k} \] Therefore, the work done can be expressed as: \[ W = (3 \hat{i} + c \hat{j} + 2 \hat{k}) \cdot (4 \hat{i} - 2 \hat{j} + 3 \hat{k}) \] 3. **Calculate the dot product:** The dot product is calculated by multiplying the corresponding components and summing them up: \[ W = (3 \cdot 4) + (c \cdot -2) + (2 \cdot 3) \] Simplifying this gives: \[ W = 12 - 2c + 6 \] Thus, we have: \[ W = 18 - 2c \] 4. **Set the work done equal to 6 Joules:** According to the problem, the work done is 6 Joules: \[ 18 - 2c = 6 \] 5. **Solve for \( c \):** Rearranging the equation: \[ 18 - 6 = 2c \] \[ 12 = 2c \] Dividing both sides by 2: \[ c = 6 \] ### Final Answer: The value of \( c \) is \( 6 \). ---

To solve the problem, we need to find the value of \( c \) in the force vector \( \vec{F} = 3 \hat{i} + c \hat{j} + 2 \hat{k} \) given that the work done by this force during a displacement \( \vec{d} = 4 \hat{i} - 2 \hat{j} + 3 \hat{k} \) is 6 Joules. ### Step-by-step Solution: 1. **Write down the formula for work done:** The work done \( W \) by a force \( \vec{F} \) over a displacement \( \vec{d} \) is given by the dot product: \[ W = \vec{F} \cdot \vec{d} ...
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Dot product of two vectors overset(rarr)A and overset(rarr)B is defined as overset(rarr)A.overset(rarr)B=aB cos phi , where phi is angle between them when they are drawn with tails coinciding. For any two vectors . This means overset(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors overset(rarr)A and overset(rarr)B also called the cross product, is denoted by overset(rarr)A xx overset(rarr)B . As the name suggests, the vector product is itself a vector. overset(rarr)C=overset(rarr)A xx overset(rarr)B then C=AB sin theta , overset(rarr)A=hat i+ hat j-hatk and overset(rarr)B=2 hat i +3 hat j +5 hat k angle between overset(rarr)A and overset(rarr)B is

Dot product of two vectors overset(rarr)A and overset(rarr)B is defined as overset(rarr)A.overset(rarr)B=AB cos phi , where phi is angle between them when they are drawn with tails coinciding. For any two vectors . This means ovsert(rarr)A . overset(rarr)B=overset(rarr)B. overset(rarr)A that . The scalar product obeys the commutative law of multiplication, the order of the two vectors does not matter. The vector product of two vectors overset(rarr)A and overset(rarr)B also called the cross product, is denoted by overset(rarr)A xx overset(rarr)B . As the name suggests, the vector product is itself a vector. overset(rarr)C=overset(rarr)A xx overset(rarr)B then C=AB sin theta , For non zero vectors overset(rarr)A, overset(rarr)B, overset(rarr)C,|(overset(rarr)Axxoverset(rarr)B).overset(rarr)C|=|overset(rarr)A||overset(rarr)B||overset(rarr)C| holds if and only if

Let overset(rarr)C = overset(rarr)A+overset(rarr)B then :

The magnitude of the vector product of two vectors and may be : overset(rarr)A and overset(rarr)B

Projection of overset(rarr)P on overset(rarr)Q is :

The angle between vector (overset(rarr)Axxoverset(rarr)B) and (overset(rarr)B xx overset(rarr)A) is :

The angle between vector (overset(rarr)Axxoverset(rarr)B) and (overset(rarr)B xx overset(rarr)A) is :

What is meant by DNA overset(a)(rarr) RNA overset (b)(rarr) Protein?

what is the angle between (overset(rarr)P+overset(rarr)Q) and (overset(rarr)P+overset(rarr)Q) ?

Are the magnitude and direction of overset(rarr) A- overset(rarr)B same as that overset(rarr)B-overset(rarr)A ?

VMC MODULES ENGLISH-INTRODUCTION TO VECTORS & FORCES -level 2
  1. Consider a system of two vectors overset(rarr)a=3hat i +4 hat j, ove...

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  2. The angle between vector (overset(rarr)Axxoverset(rarr)B) and (overset...

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  3. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  4. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  5. Dot product of two vectors overset(rarr)A and overset(rarr)B is defi...

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  6. Maximum and minimum values of the resultant of two forces acting at a ...

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  7. A force ( 3 hati +4 hat j) newton acts on a body and displaces it by...

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  8. If a vector 2 hat (i) + 3 hat(j) + 8 hat(k) is perpendicular to the ve...

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  9. What is the torque of a force overset(rarr)F=(2 hat i -3 hat j +4 hat ...

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  10. The magnitudes of the X and Y components of overset(rarr)P are 7 and...

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  11. A car is going in south with a speed of 5m//s. To a man sitting in car...

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  12. The area of parallelogram represented by the vectors overset(rarr)A =...

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  13. The river 500 m wide is flowing with a current of 4kph. A boat starts ...

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  14. An aeroplane takes off from Mumbai to Delhi with velocity 50 kph at an...

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  15. If the system is in equilibrum, find the Normal Reaction between 2kg a...

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  16. The string and the pulley are massless and the system is in equilibriu...

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  17. The block is always at rest, the maximum force which can be applied fo...

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  18. A force of 200N is applied as shown in the figure on block of 3 kg. Th...

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  19. A river is flowing with a velocity of 2m/s. If the width of river in 1...

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  20. A force 3hat i+4 hat j - 5 hatk N is acting on a particle. If the ve...

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