A vacuum cleaner has an energy input of 6.5 kWh and an energy output of 5.8 kWh. The efficiency of the vacuum cleaner, to the nearest percentage, is

What are two things that the amount of gravitational force depend on

Which is greater, the mass of the compounds before a chemical reaction or the mass of the compounds after a chemical reaction? The mass of the compounds before is greater. The mass of the compounds after is greater.

What is a form of oxygen that has three oxygen molecule instead of the usual two?

If you heat a thin, circular ring in the oven, does the rings hole get larger or smaller?

2.1kilograms into grams (1000g=1kg)

Convert 1.5 radian into milliradians.

Whats the core of electromagnet made of?

Ultraviolet light emits a total of 2.5 * 10^-17 J of light at a wavelength of 9.8 * 10^-7 m. How many photons does this correspond to?

3. A ray of light incident on one face of an equilateral glass prism is refracted in such a way that it emerges from the opposite surface at an angle of 900 to the normal. Calculate the i. angle of incidence. ii.

What would happen to the stratosphere if humans were to increase the amount of ozone within it?