7. Find average speed if a man travels at speed of 24 kmph up and 36 kmph down at an altitude of 200m. a) 28.8 b) 28 c) 27 d) 28.6

• In such cases,
  
  average speed = 2*24*36/(24+36) = 2*24*36/60 = 144/5 kmph = 28.8 kmph .. option a
• 13 years agoHelpfull: Yes(6) No(0)
• avg speed= total distance/total time taken
  time during upwards be t1 and down is t2.
  24*5/18=6.67 m/s, t1=200/6.67=30 sec.
  36*5/18=10 m/s, t2=200/10=20 sec
  avg speed = 400/50 =8 m/s = 8*18/5= 28.8 kmph
• 13 years agoHelpfull: Yes(1) No(2)
• v can use this here 2*x*y/(x+y)to find average speed
  
• 13 years agoHelpfull: Yes(0) No(2)
• can anybody tell me that the value of altitude 200m .is there no use of this value
  
• 10 years agoHelpfull: Yes(0) No(0)