Physics

# If the units of length and force are increased by four times, the unit of energy will be increased by:

$1500$%

##### SOLUTION

Energy $=ML^{2}T^{-2}=Force\times length$

$L'=4L$
$F'=4F$

% Increase $=\dfrac{16(Force\times length)-(force\times length)}{(force \times length)}\times 100$

$= 1500$%

You're just one step away

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

#### Realted Questions

Q1 Single Correct Medium
When $CO_{2}(g)$ is passed over red-hot coke it partially gets reduced to $CO(g)$. Upon passing $0.5$ litre of $CO_{2}(g)$ over red-hot coke, the total volume of the gases increased to $700\ mL$. The composition of the gaseous mixture at STP is :
• A. $CO_{2} = 200\ mL; CO = 500\ mL$
• B. $CO_{2} = 350\ mL; CO = 350\ mL$
• C. $CO_{2} = 0.0\ mL; CO = 700\ mL$
• D. $CO_{2} = 300\ mL; CO = 400\ mL$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q2 Single Correct Medium
A force $F$ is given by $F = at + bt^2$, where t is time, the dimensions of $a$ and $b$ are :
• A. $[MLT^{-3}]$ and $[MLT^{-4}]$
• B. $[MLT^{-3}]$ and $[ML^-2T^{-4}]$
• C. $[MLT^{-4}]$ and $[MLT^1]$
• D. $[MLT^{-3}]$ and $[ML^2T^{-4}]$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q3 Single Correct Medium
In the relation $P = \frac{a}{\beta}e^-\frac{az}{k\theta}, p$ is the pressure, z the distance, k is Boltzmann constant and $\theta$ is the temperature, the dimensional formula of $\beta$ will be
• A. $M^0L^2T^0$
• B. $ML^2T$
• C. $ML^0T^{-1}$
• D. $ML^2T^{-1}$

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q4 Single Correct Medium
The accuracy of measurement also lies in the way the result is expressed. The number of digits to which a value is to be expressed is one digit more than number of sure numbers. Rules do exist to deal with number of digits after an operation is carried out on the given values. The error can be minimised by many trials and using the correct methods and instruments.
The number of significant figures can reduces in
• B. Subtraction
• C. Multiplication
• D. Division

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020

Q5 Subjective Medium
Name the three convenient units used to measure length ranging from very short to very long value. How are they related to the S.I. unit?

Asked in: Physics - Units and Measurement

1 Verified Answer | Published on 18th 08, 2020