Trong thực nghiệm nhiễu xạ qua 1 khe hẹp, bề rộng khe là 2.10-5 m, màn quan sát đặt cách khe 0,5 m. Chiếu ánh sáng có bước sóng 480 nm xuyên qua khe và thấy có nền nhiễu xạ trên màn quan sát. Tính bề rộng của vân sáng liền kề vân sáng trung tâm.

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)

Which of the following is not a part of the respiratory system? a. pharynx b. trachea c. pancreas d. larynx hurrim timed

Standing side by side ,you and a friend step off a bridge at different times and fall for 1.6s to the water below. your friend goes first, and you follow after he has dropped a distance of 2.0m. when your friend hits the water, is the seperation between the two of you 2.0m or more than 2.0m? verify your answer with a calculation.