An escalator between two floors in a shop consists of steps that are each 30 cm high and 40 cm deep.There are 20 steps between the floors.The escalator moves a…

Thorium-232 ( Th) is an unstable nuclide that decays through a sequence of radioactive emissions to form a stable nuclide of lead. All of the emissions during this sequence are…

Which statement about waves is correct? Answer: 15) F The only correct statement is F. Ultrasonic waves, like sound waves, are longitudinal.

A champion weightlifter raises a 200 kg set of weights from the floor to above his head in one movement. The bar is lifted through a vertical distance of 1.8…

Uranium-238 is a naturally-occurring alpha emitter. It can be used in the manufacture of the isotope plutonium-239, during which it is bombarded by neutrons. The process of converting a nucleus…

The diagram represents a satellite communication link between two points on Earth. Thedistances between the transmitting station, the satellite and the receiving station are shown.The frequency of the waves used…

The diagram shows the only four forces acting on a model aircraft of mass 2.0 kg whilst flying. Which line in the table states the horizontal and vertical accelerations of…