DP Physics (last assessment 2024)

Test builder »

Question 17N.2.SL.TZ0.3a.ii

Select a Test
Date November 2017 Marks available [Maximum mark: 2] Reference code 17N.2.SL.TZ0.3a.ii
Level SL Paper 2 Time zone TZ0
Command term Calculate Question number a.ii Adapted from N/A
a.ii.
[Maximum mark: 2]
17N.2.SL.TZ0.3a.ii

Electrical resistors can be made by forming a thin film of carbon on a layer of an insulating material.

A carbon film resistor is made from a film of width 8.0 mm and of thickness 2.0 μm. The diagram shows the direction of charge flow through the resistor.

(a.ii)

The film must dissipate a power less than 1500 W from each square metre of its surface to avoid damage. Calculate the maximum allowable current for the resistor.

[2]

Markscheme

power = 1500 × 8 × 10–3 × 0.032 «= 0.384»

«current ≤ power resistance = 0.384 82 »

0.068 «A»

 

Be aware of ECF from (a)(i)

Award [1] for 4.3 «A» where candidate has not calculated area