A paper weight is dropped from the roof of a block of multi storey flats. each storey being 3 metre high. it passes the ceiling of the 20th storey at 30m/s. if g=10m/s2, how many storeys does the flat have?

2. What is the speed (v) of a wave that has a wavelength (a) of 2 m and a frequency (f) of 6 Hz?

a zookeeper had a difficult time moving the elephant back inside for the evening. The elephant is difficult to move because a. It has unbalanced forces acting on it. b. It has high a high amount of momentum. c. It has balanced forces acting on it. d.

Which quantity is a vector quantity? acceleration mass speed volume

You are asked to design a retroreflector using two mirrors that will reflect a laser beam by 180 degrees independent of the incident direction of the beam. What should be the angle between the two mirrors?

Mirrors effectively operate because of this behavior of light

The mass is increased by a factor of four. What is true about the period? Choose the best answer. The period remains unchanged. The period increases by a factor of four. The period is halved. The period doubles.

What does law of conservation of mass mean?

Why do substances with free electrons make the best conductors.

Which of the following is evidence that groundwater causes erosion and deposition?

Which project involved the goal of orbiting a manned spacecraft around earth? A. Mercury B. Apollo C. Gemini D. Skylab