Answer:
Average speed = 40.50 km/h (Approx)
Explanation:
Distance = Time × Speed
Total distance = (40/60) 50 + (8/60) 70 + (35/60) 35
Total distance = 33.33 km + 9.33 km + 20.17 km
Total distance = 62.80 km
Average speed = Total distance / Total time taken
Average speed = 62.80 / [(40+8+35+40)/60]
Average speed = 62.80 / 1.55
Average speed = 40.50 km/h (Approx)
T1=S/V1T2=Ttot-T1=(2S/Vtot)-S/V1V2=S/T2 = S / (2S/Vtot-S/V1)Simplify in V2 = V1Vtot/(2V1-Vtot) = 48 * 90 / 6 = 720 km/hr
Answer:
A. The ball has a negative acceleration on the way up and a positive acceleration on the way down.
Explanation:
- When a ball is thrown up vertically then the acceleration due to gravity always acts in a direction towards the center of the earth. So here when an object is thrown vertically upwards then the acceleration due to gravity acting in a downward direction which is opposite to the direction of motion of the object hence taken as negative with respect to the displacement.
- When the ball reaches at the top height its speed becomes zero and then it returns back towards the earth. While coming down the direction of the object's displacement is same as the direction of acceleration due to gravity.
<span>B) The period increases and the frequency decreases.
Hope this helps!
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