If the half-life of niobium-91 is 680 years, how long will it take for the decay described in the previous question?

Newton's third law says that for every action force there is a reaction force which is a. equal and opposite. b. equal and in the same direction. c. large enough to make the net force zero. d. twice as large and in the opposite direction.

A hypothesis is an assumption or a best guess that

Downhill skiers race over a course that's 3,500 m long in 2 minutes, 10 seconds. What is their approximate average speed for this course? O A. 1.67 m/s O B. 26.9 m/s O c. 19.2 m/s O D. 1,667 m/s

A small rubber wheel is used to drive a large pottery wheel, and they are mounted so that their circular edges touch. The small wheel has a radius of 2.0 cm and accelerates at the rate of 7.

A family goes on a walk beside a large river. What would most likely happen to the river if the oceans did not exist?

A uniformly charged conducting sphere of 1.1 m diameter has a surface charge density of 6.2 µC/m2. (a) Find the net charge on the sphere. (b) What is the total electric flux leaving the surface of the sphere?

A blow-dryer and a vacuum cleaner each operate with a voltage of 120 V. The current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 5.7 A. Determine the power consumed by (a) the blow-dryer and (b) the vacuum cleaner.

4. A 40 kg child and a 30 kg child want to balance themselves on a 4 meter, 50 kilogramn see-saw. Where should the fulcrum be placed?

A 2-kg object is dropped from a height of 1000 m. What is the force of air resistance on the object when it reaches terminal velocity

What is the approximate increase in size from a 1 w to a 2w carbon resistor?