Which of the following statements correctly identifies an example of t...
A scalar multiplied by a scalar will produce another scalar. For instance, distance divided by time is equal to speed, which is a scalar. In the case of power, energy divided by time is equal to power. Statement III is true.
A vector multiplied by a scalar is representative of the scalar product or the dot product and will always produce a vector. The scalar product of two vectors

can be constructed by taking the component of

in the direction of

and multiplying it times the magnitude of

and it can be expressed as AB cos θ.
Torqueis not an example of the scalar product of vectors since it is equal to rF sinθ. A correct example of the dot product would be work, which is equal to Fd cos θ. Therefore, statement I is not true.
Vector multiplied by a vector is representative of the vector product or the cross product and will produce a vector or scalar. The magnitude of the vector product of

can be constructed by taking the product of the magnitudes of

multiplied by the sine of the angle between them.
Magnetic force is an example of the vector cross product, so statement II is true. Therefore, the correct answer is that statements II and III are true.
View all questions of this test
Which of the following statements correctly identifies an example of t...
Understanding Scalar and Vector Products
To clarify why option 'C' is correct, let's analyze the statements related to scalar and vector products.
Statement I: Vector and Scalar - Torque
- Torque is defined as the cross product of a vector (lever arm) and a force vector.
- It results in a vector quantity, not a scalar.
- Therefore, this statement is incorrect for identifying scalar or vector processes.
Statement II: Vector and Vector - Magnetic Force
- Magnetic force on a charged particle moving in a magnetic field is indeed a vector quantity.
- It is derived from the cross product of the velocity vector and the magnetic field vector.
- Hence, this statement correctly identifies a vector and vector process.
Statement III: Scalar and Scalar - Power
- Power is defined as the rate at which work is done or energy is transferred.
- It can be computed as the dot product of force (vector) and velocity (vector), resulting in a scalar quantity.
- Hence, this statement accurately identifies a scalar product.
Conclusion
Based on the analysis:
- I is incorrect.
- II is correct (Vector and Vector: Magnetic Force).
- III is also correct (Scalar and Scalar: Power).
Thus, the correct answer is option 'C' (II and III).