PHYSICS

JAMB 2012 - Question 20

Physics 2012 JAMB Past Questions - Question 20: Two metals P and Q are heated through the same temperature difference .If the ratio of the linear expansitives of P to Q is 2:3 and the ratio of their length is 3:4 respectively ,the ratio of the increase in length of P to Q is

Choose the correct answers from the options given.
Two metals P and Q are heated through the same temperature difference .If the ratio of the linear expansitives of P to Q is 2:3 and the ratio of their length is 3:4 respectively ,the ratio of the increase in length of P to Q is
A:
B:
C:
D:
Examkits App

Examkit's JAMB CBT App

Practice JAMB offline with our Online, PC and Mobile App

  • ✅ 25+ years of past questions (2000 to 2025)
  • ✅ Video solutions and explanation to questions
  • ✅ E-library
  • ✅ Study by topic
  • ✅ And more.

Correct Answer

A

Explanation

To find the ratio of the increase in length of metals P and Q, we can use the formula for linear expansion:

ΔL = α * L * ΔT

Where:
ΔL is the change in length,
α is the linear expansivity,
L is the original length, and
ΔT is the change in temperature.

Let's assume that the change in temperature (ΔT) is the same for both metals P and Q.

Given that the ratio of the linear expansivities of P to Q is 2:3, we can assign values to them as follows:
Let the linear expansivity of P be 2x, and the linear expansivity of Q be 3x.

Given that the ratio of their lengths is 3:4, we can assign values to them as follows:
Let the length of P be 3y, and the length of Q be 4y.

Now, let's calculate the change in length for each metal:

For metal P:
ΔL_P = (2x) * (3y) * ΔT = 6xyΔT

For metal Q:
ΔL_Q = (3x) * (4y) * ΔT = 12xyΔT

Therefore, the ratio of the increase in length of P to Q is:
ΔL_P : ΔL_Q = 6xyΔT : 12xyΔT = 1:2

So, the ratio of the increase in length of P to Q is 1:2.

Frequently Asked Questions

Examkits is a JAMB CBT practice platform that provides over 20 years of past questions, Post UTME questions, and detailed video solutions to help students prepare for their exams.

You can practice JAMB past questions online, on Android, or on a desktop using the Examkits app. Just register on our website and choose your preferred device.

Yes. Our Android and Windows versions support offline usage. Once downloaded and activated, no internet is required to use most of the features.

Yes, Examkits provides detailed video explanations for all JAMB past questions from 2000 to 2024, helping students understand how to solve each problem.

Examkits offers free practice for some subjects. However, full access requires a one-time affordable activation fee for each version of the app.