If the electronic structure of a solid substance consists of a valence band that is completely filled with electrons and there is a large energy gap to the next set of orbitals, then this substance will be a (n

A less common type of radioactive particle emitted is the positron. If potassium-38 forms argon-38 by positron emission, the number of a positron is and the charge is

What is the entropy criterion for spontaneous change in an isolated system?

What type of rock is formed from the weathered remains of other rocks?

Why don't animal cells need chloroplasts? A) Animals do not make their own food. B) Animal cells make their own chlorophyll. C) Animal cells collect sunlight another way. D) Animals use photosynthesis to make their own food.

A swimmer heading directly across a river 200 m wide reaches the opposite bank in 6 min 40 s. she is swept downstream 480 m.

A transparent film laminated to a fabric is identified in the study material as a. stretch fabric. b. PVC. c. a skin. d. two-faced fabric

Light from the sun travels through space to Earth's atmosphere. Which will light waves do when they move from empty space into matter made up of different gases? A. move at the same speed B. move faster as they transmit C. slow down and refract D.

A 12.5 kg box sliding on a frictionless flat surface tuns into a fixed spring which compresses at a distance x = 14.1 cm. the spring constant is 94.5 kN/m Find the initial speed of the box

An earth scientist who studies hydrosphere

In 1991 four English teenagers built an eletric car that could attain a speed of 30.0m/s. Suppose it takes 8.0s for this car to accelerate from 18.0m/s to 30.0m/s. What is the magnitude of the car's acceleration?