#### Passage

These questions consist of two statement, each printed as assertion and reason. While answering these question you are required to cheese any one of the following five responses.
Physics
##### ASSERTION

The error in the measurement, of radius of the sphere is $0.3$% . The permissible error in its surface area is $0.6$%

##### REASON

The permissible error is calculated by the formula $\dfrac {\Delta A}{A} = \dfrac {4\Delta r}{r}$

Assertion is correct but Reason is incorrect

##### SOLUTION

Area of the sphere, $A = 4\pi r^{2}$

% error in area $= 2 \times$ % error in radius

i.e., $\dfrac {\Delta A}{A} \times 100 = 2\times \dfrac {\Delta r}{r} \times 100$

$= 2\times 0.3$ % $= 0.6$%

But $\dfrac {\Delta A}{A} = 4 \dfrac {\Delta r}{r}$ is false.

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Assertion & Reason Hard Published on 18th 08, 2020
Physics

# Assertion: The dimensional formula for relative velocity is same as that of the change in velocity.Reason: Relative velocity of P w.r.t. Q is the ratio of velocity of P and that of Q.

Assertion is true but reason is false

##### SOLUTION

Relative velocity which is vector subtraction of two velocities will also be a vector of the form of velocity so, its dimensional formula will remain unchanged. Relative velocity is measured not by calculating ratio but by calculating difference.

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Single Correct Hard Published on 18th 08, 2020
Questions 244531
Subjects 8
Chapters 125
Enrolled Students 199

#### Realted Questions

Q1 Single Correct Medium
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Q4 Single Correct Medium
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1 Verified Answer | Published on 18th 08, 2020

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1 Verified Answer | Published on 18th 08, 2020