Date | November 2014 | Marks available | 1 | Reference code | 14N.1.SL.TZ0.7 |
Level | Standard level | Paper | Paper 1 | Time zone | Time zone 0 |
Command term | Question number | 7 | Adapted from | N/A |
Question
An object of mass m1 has a kinetic energy E1. Another object has a mass m2 and kinetic energy E2. The objects have the same momentum. What is the ratio \(\frac{{{E_1}}}{{{E_2}}}\)?
A. 1
B. \(\sqrt {\frac{{{m_2}}}{{{m_1}}}} \)
C. \(\frac{{{m_2}}}{{{m_1}}}\)
D. \({\left( {\frac{{{m_2}}}{{{m_1}}}} \right)^2}\)
Markscheme
C
Examiners report
A was a popular choice. Candidates should be taught the conceptual difference between momentum and kinetic energy and realise that if the momentum of two moving objects of different mass is the same, then their kinetic energy can never be the same.