1 You may sometimes find it difficult to get up from the sofa after watching a TV programme.
Assuming the force of gravity acts between the centre of your body and the centre of the sofa,
estimate the attraction between you and your sofa.
ON
2
Calculate the size of the gravitational pull of a sphere of mass 10 kg on a mass 2.0 kg
their centres are 200 mm apart.
What is the force of the 2.0 kg mass on the 10 kg mass?
when

Occurs when an energy source transfers heat directly to another subject space; an example would be an object becoming warm by sitting in the sunshine

If element x has 99 protons how many electrons does it have

Antireflective coatings on solar cells are often made by applying a thin film of silicon nitride (sinx), which has an index of refractive of 1.2, on the top of the silicon solar cell, which has a refractive index of about 3.5. however, the sun emits radiation of various wavelengths which the solar cell absorbs, and the antireflective coating can only absolutely minimize the reflection of one of these wavelengths. the coating thickness is chosen to reduce the reflection of green/yellow light (e = 2.2 ev), which is the most intense color in the solar spectrum (shown below). which of the following coatings would minimize reflection of green/yellow light? the answer is 820 nm how? what is the angular width of the central maximum of an electron traveling at 2 x 108 m/s going through a single slit of width 1 mm.