Rain is falling vertically with a speed of 20 m/s. A person is running in the rain with a speed of 10m/s from north to south. In which direction should be hold his umbrella?Explain.​

On mars a rock falls an unknown vertical distance from a resting position and lands in a crater. if it takes the rock 2.5 seconds to fall, how high is the cliff the rock fell from? mars' surface gravity is 3.8 m/s2.

Along wire of diameter 1 mm is submerged in an oil bath of temperature ∞ 31°c. the wire has an electrical resistance per unit length of 0.01 ω/m. if a current of 103 a flows through the wire and the convection coefficient is 500 w/m2·k, what is the steady-state temperature of the wire? from the time the current is applied, how long does it take for the wire to reach a temperature that is within 1°c of the steady-state value? the properties of the wire are 8000 kg/m3, 500 j/kg·k, and 20 w/m·k.

According to rutherford's nuclear theory, most of the volume of an atom is , so the volume of a hydrogen atom cannot be mostly due to the proton.according to rutherford's nuclear theory, the core of an atom (nucleus) contains most of of an atom and is , so the majority of the mass of a fluorine atom cannot be due to its nine electrons.according to rutherford's nuclear theory, the number of negatively charged particles outside the nucleus the number of positively charged particles within the nucleus, so a nitrogen atom has 7 protons and 7 electrons, while a phosphorous atom cannot have 15 protons and 150 electrons.word bank: dense, empty space, more than, mass, particles, the same as, less than, positively charged, negatively charged