5. A girl whose mass is 52 kg exerts a force of 25 N on a ball. Calculate the a) acceleration of the ball.
b) the final velouhcity of the ball if the time it takes the ball to reach a
distance of 20 m is 3 minutes.
c) work done by the girl.
d) power of the girl.

Aroll in a paper machine is powered by a separately excited dc machine. operating point 1 (under load): the roll typically operates at 764 rpm and must provide 301 nm of torque to oppose the load of the paper. the armature voltage is 230v for this operating point operating point 2 (no load): when the load is removed the speed of the roll increases to 900 rpm (the field characteristics are unchanged) la ea dev m (a) calculate the maximum torque (units of nm) that the motor can supply with this applied voltage (b) calculate the value of the armature resistance, ra (in ohms) (c) at operating point 1 (loaded condition), the field current, i, and the total input power (armature field), are measured to be to be 10 a and 28,600 w respectively. use this information to calculate the value of the field resistance, rf (in ohms). (d) (d) at operating point 1 (loaded condition), calculate the motor efficiency. express your answer as a percent to at least 2 significant digits. (d) if the field voltage is reduced by 1/2, calculate the new stall torque (in nm) of the motor (f). if the field voltage is reduced by 1/2, calculate the new no-load speed (in rad/sec)

Complete the statement about memory improvement. ( )involves organizing and breaking down information into easier groups to expand capacity. rehearsal is the verbal repetition of information. these techniques are especially important for the improvement of ( ) memory.

Blood pressure the total amount of blood the heart pumps in one minute 2. cardiac output the number of times your heart beats in a minute 3. dilate the amount of blood that the heart can pump in a single beat 4. heart rate the force exerted on the walls of the blood vessels by the blood that moves through them 5. stroke volume to widen or get larger in size