A hot water dispenser is used to heat enough water for one cup at a time. The rating plate for the hot water dispenser is shown.
Model: 1-KUPPA
3-5 kW
230 V
50 Hz
The hot water dispenser takes 26 s to heat enough water for one cup.
(a) Show that the energy supplied to the hot water dispenser during this
time is 91 000 J.

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.

Suppose a soccer ball is kicked from the ground at an angle 20.0º above the horizontal at 8.00 m/s. the y-velocity is determined to be 2.74 m/s. how long will the ball be in the air? assume the ball lands at the same height at which it was kicked.

Cyclotrons are widely used in nuclear medicine for producing short-lived radioactive isotopes. these cyclotrons typically accelerate h- (the hydride ion, which has one proton and two electrons) to an energy of 5 mev to 20 mev. this ion has a mass very close to that of a proton because the electron mass is negligible—about 1 2000 of the proton’s mass. a typical magnetic field in such cyclotrons is 1.9 t. (a) what is the speed of a 5.0-mev h-? (b) if the h- has energy 5.0 mev and b = 1.9 t, what is the radius of this ion’s circular orbit?