Mechanical Engineering Answers

Solar radiation is incident on a semi-transparent body at a rate of 900 W/m2 . If 150 W/m2 of this incident radiation is reflected back and 225 W/m2 is transmitted across the body, determine the absorptivity of the body. 

2.1 For the circuit shown in Figure 2(a), the switch was initially at Position 2: 2.1.1 Write the mathematical expressions for the transient behavior of the voltage 𝑣𝑐 and the current 𝑖𝑐 if the capacitor was initially uncharged and the switch is thrown into position 1 at 𝑡=0 s. (5) 2.1.2 Write the mathematical expressions for the voltage and the current if the switch is moved to position 3 at 𝑡=10 ms (assume no leakage current). (5) E 24V 8kΩ 0.08µF R1 R2 C 20kΩ iC vC + - 1 2 3 Figure 2(a) E 36V 8kΩ 2H R1 R2 L 4kΩ iL vL + - vR2 + - + vR1 - Figure 2(b) Figure 2: 2.2 For the circuit in Figure 2 (b): 2.2.1 The switch is closed at 𝑡=0 s. Write the mathematical expressions for 𝑖𝐿 , 𝑣𝐿 , 𝑣𝑅1 , 𝑣𝑅2 within five time constants of the storage phase. (5) 2.2.2 The switch is opened after five time constants of the storage phase, write the mathematical expressions for 𝑖𝐿 , 𝑣𝐿 , 𝑣𝑅1 , 𝑣𝑅2 . (5) [20]

Determine the average power delivered to R4 in figure 3 Figure 3 [20]

QUESTION 1 Determine the Thévenin equivalent circuit of the network at terminals a-b for the circuit shown in Figure 1. E R1 8Ω C1 16Ω L2 8Ω R2 L1 2Ω a b 12V∠0° 5Ω Thévenin Figure 1 [10]

 A ball is thrown vertically upward with a speed of 15 m/s. Determine the time of flight when it 

returns to its original positio

Why is PID suboptimal in case of non-linearities? And also what problems may arise if the differential part is missing in a PID?

Obtain input from a user. ( only 1 input ) and Determine the input as follows ( Letter A - Z, a - z ), Number ( 0 - 9 ), Special. Character )

If the input is a Letter ( determine if ( Vowel or Consonant )

Output the result.

Why is there a 1/2 in from on the vi+vf?