Question

Time Allowed: 20 minutes Question: The search light shown in Figure 1 casts a spot of light along the face of the wall that is located 120m from the searchlight. Determine the magnitude of the velocity and acceleration at which the point appears to travel across the wall at the instance when 0 = 40 degrees. The searchlight is rotating about Z axis at the constant rate of de/dt = 2 rad/s Wall . 120 m Figure 1 de/dt 2 rad/s Solution ---

Answer 1

20 x= 120 tn 12D velocbyv |20 dec do - ctt as de dt Contat -2 rad lesc ひ= 24089 U 120 x2 Sec0 occlondtap du 240 x 2 Sec0 Sectome de a-480 Bec tang de a=960 Sec0an 8 ms2 at 0 40 CSec 40) 408.38ms V = 240 a- 960 Sec4 o) tmq0 = 1332.70ms L ひ=408.98mst as1372-70 ms whano u40