About 35 electron volts of energy is required to ionize an air molecule. A 2 MeV radioactive particle passing through the air would therefore be expected to result in the ionizing of approximately ___ air molecules.

Which seasons are the northern and southern hemispheres experiencing in the image? it is summer in both the northern and southern hemispheres. it is summer in the northern hemisphere and winter in the southern hemisphere. it is winter in both the northern and southern hemispheres. it is winter in the northern hemisphere and summer in the southern hemisphere.

A1-lb collar is attached to a spring and slides without friction along a circular rod in a vertical plane. the spring has an undeformed length of 5 in. and a constant k =25 lb/ft. knowing that the collar is released from being held at a determine, the speed of the collar and the normal force between the collar and the rod as the collar passes through b.

Abatter hits a 0.140-kg baseball that was approaching him at 30 m/s and, as a result, the ball leaves the bat at 40 m/s in the reverse of its original direction. the ball remains in contact with the bat for 2.0 ms. what is the magnitude of the average force exerted by the bat on the ball?