Assertion : A negative acceleration of a body can be associated with a ‘slowing down’ of the body.
Reason : Acceleration is a vector quantity.

Q. Assertion: $\overrightarrow{\tau }=\overrightarrow{r}\times \overrightarrow{F}but\overrightarrow{\tau }\ne \overrightarrow{F}\times \overrightarrow{r}.$
Reason: Cross product of a vector is commutative.

Q. Assertion: Vector product of two vectors is an axial vector.
Reason: For a body under rotation, if $\overrightarrow{v}=$ instantaneous velocity, $\overrightarrow{r}=$ radius vector and $\overrightarrow{\omega }=$ angular velocity, then $\overrightarrow{\omega }=\overrightarrow{v}\times \overrightarrow{r}$.

Q. Assertion: If dot product and cross product of $\overrightarrow{A}$ and $\overrightarrow{B}$ are zero, it implies that one of the vector $\overrightarrow{A}$ and $\overrightarrow{B}$ must be null vector.
Reason: Null vector is a vector with zero magnitude.

Q.

Read the assertion and reason carefully to mark the correct option out of the options given below :

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c) If assertion is true but reason is false.

(d) If the assertion and reason both are false.

(e) If assertion is false but reason is true.

Assertion: Acetic acid does not undergo haloform reaction.

Reason: Acetic acid has no alpha hydrogens.

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:
Assertion: Short wave bands are used for transmission of radio waves to a large distance.
Reason : Short waves are reflected by ionosphere
(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.
(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.
(c)If assertion is true but reason is false.
(d)If the assertion and reason both are false.
(e)If assertion is false but reason is true.