WAEC Physics 2022 Objective — Question 40
Question 40 of 50 from the West African Examinations Council (WAEC) Physics 2022 Objective paper, with the correct answer and a full explanation.
Advertisement
The diameter of a brass ring at 30°C is 50.0cm. To what temperature must this ring be heated to increase its diameter to 50.29cm? [linear expansivity of brass=1.9×10⁻⁵ K⁻¹]
- A. 152.6°C
- B. 182.6°C
- C. 306.1°C
- D. 335.3°CCorrect
Explanation
Δl=αl₀Δθ. Δθ=Δl/(αl₀)=(50.29−50)/(1.9×10⁻⁵×50)=0.29/9.5×10⁻⁴=305.3°C. New temp=30+305.3=335.3°C.
Advertisement
Sign up free to unlock
- Score tracking
- Practice history
- Saved questions
- Progress dashboard
- Personalized sessions
- Weak-topic breakdown
…and/or go further with premium services and No Ads.