Which object has the least thermal energy? O A. A 2 kg brick at 25°C
O B. A 4 kg brick at 25°C
O C. A 2 kg brick at 20°C
D. A 4 kg brick at 20°C

Examine the drawing of a molecule. each ring represents an atom of nitrogen (n). what’s the chemical formula of this substance?

To practice problem-solving strategy 10.1 for energy conservation problems. a sled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slides a distance d1 down the slope and then covers the distance d2 along the horizontal terrain before stopping. find the coefficient of kinetic friction μk between the sled and the ground, assuming that it is constant throughout the trip.

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656(red) and 486 (blue). light from a hydrogen lamp illuminates a diffraction grating with 500 lines per mm, and the light is observed on a screen 1.50 behind the grating. what is the distance between the first-order red and blue fringes?