WAEC Physics 2010 Theory — Question 19
Question 19 of 22 from the West African Examinations Council (WAEC) Physics 2010 Theory paper, with the correct answer and a full explanation.
Advertisement
12(d) Two vertical capillary tubes of the same diameter are lowered into beakers situated at the same level, containing liquids A and B of densities 9.2x10² kgm⁻³ and 1.30x10³ kgm⁻³ respectively. A suction pump is used to withdraw air from the top of the liquid columns in the tubes by means of a T-piece arrangement until the liquid in A rises to a height of 26.0 cm. Calculate the height of the liquid in tube B.
Model answer
Density of A, PA=9.2x10²kg/m³; density of B, PB=1.3x10³kg/m³; height of A, HA=26cm; height of B, hB=? Since pressure=ρhg, and pressure at same level is equal, then: ρAhAg=ρBhBg; hB=(PA x hA)/PB = (9.2x10² x 26)/(1.3x10³) = 18.4 cm.
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.