At noon during the spring equinox, why does the sun feel hotter at the equator than it does in Alaska?​

What sort of waves exhibit the doppler effect?

Aforce of 8,480 n is applied to a cart to accelerate it at a rate of 26.5 m/s2. what is the mass of the cart?

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?