Which reasons explain why a theory would be changed or replaced

Based on the table, which isotope is best suited for use as a radioactive tracer for the body's use of calcium? calcium-40 calcium-45 calcium-47 calcium-49

A soap bubble has a diameter of 4mm. Cakculate the pressure inside it if the atmospheric pressure outside is 10^5Nm^2. The surface tension of soap = 2.8 * 10^-2N/m

Ultraviolet rays from the sun are able to reach Earth's surface because A. They require air to travel through B. They have less energy than infrared rays C. They have lower frequencies than visible light D. They can travel through empty space

A wheelbarrow is a complex machine that combines which simply marchines?

Ignore friction and air resistance. If the total mass of the roller coaster cars is 800kg, and the 50,000 N of gravitation force are acting on the roller coaster cars, what is the acceleration of the roller cars?

A cell provides 6 V to an LDR. The current through this LDR is measured and is found to be 3 A. What is the resistance of the LDR?

A car travels along eastward with a constant velocity. the magnitude of the acceleration of the car is

What is the weight of a 65 kg astronaut on mars?

When lava cools, what type of Rock forms?

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?