A110-kg tackler moving at a speed of 3.5 m/s
meets head-on (and holds on to an 85-kg halfback
moving at a speed of 5.0 m/s.
part a
what will be their mutual speed immediately after the collision?
express your answer to two significant figures and include the appropriate units.
units

What is the temperature in degrees celsius of a substance with a tempature of 49k

Your friend increases her force on the desk by 30n . she doesn't change the direction of her push . what happens to the net force on the desk .will the desk accelerate

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light