The slope of the illustrated plane is increased until, at θ = 21°, the penguin is just on the verge of sliding. What is the coefficient of static friction between the penguin and the plane?

Asmall electric heater, immersed in 80g of water in a calorimeter of 40j/k raises the temperature from 10.5 degree celsius to 25 degree celsius in 12 minutes. using the same apparatus with 50g of oil instead of water, it is found that the temperature of oil rises from 7 degree celsius to 27 degree celsius in 10 minutes. find specific heat capacity of the oil.

Calculate 9 ∙ 10-5 divided by 3 ∙ 10-9. (box after the "10" in answer is for the

The voltmeter reads 117 v and ammeter reads 0.13 a .if the resistance of ammeter and voltmeter are 9 kilo ohm and 0.015 ohm respectively ,find the value of r. 3marks