TRB PHY Unit 1

Which of the following is correct?

a) curl r = 0

b) div r= 0

• a,b both correct

• a only correct

• b only correct

• a,b both are wrong

If A and B are irrotational then A x B is

• Irrotational

• Rotational

• Solenoidal

• Vector

If A and B are orthogonal matrices, then

• AB is orthogonal

• AB is not orthogonal

• AB is null matrices

• AB is unit matrics

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

• A

• B

• C

• D

Which of the following relation is correct

• I only

• II only

• Both I and II

• Both are wrong