A car's horn is honking at a constant frequency. as the car is driving away from you the pitch you hear will be what is heard by the driver of the car A. lower than
B. higher than
C. the same as
D. exactly twice

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

What is meant by the statement" the melting poin of glycerine is 13 degree celsius

If gases like carbon dioxide and methane make up less than 1% of the total atmosphere, why is it important for scientists to monitor changes in percentages of these gases?