Gravitation- numerical probelm, Physics

A ball dropped from a balloon at rest clears a tower  81m high during the last quater second of its journey. Find the height of the balloon and the velocity of the body when it reaches the ground.

WHAT IT MEANS- LAST QUATER SECOND OF ITS JOURNEY.
 
Solution) The last quarter of the jouney menas 1/4th of the total time it requires in its total journey.

Let total time be 4t, u = 0.

So, v at 3t = 3gt, and at 4t = 4gt.

by v² = u² + 2as,

16g²t² = 9g²t² + 2g(81)

7g²t² = 162g

7gt2 = 162

t² = 162 / 7g

t = 1.5 sec.

but time is 4t = 6 sec.

So velocity on reaching = 4gt = 58.8 m/s

With this velocity, height of fall = 2t(58.8) = 705.6m

Posted Date: 3/11/2013 7:13:32 AM | Location : United States







Related Discussions:- Gravitation- numerical probelm, Assignment Help, Ask Question on Gravitation- numerical probelm, Get Answer, Expert's Help, Gravitation- numerical probelm Discussions

Write discussion on Gravitation- numerical probelm
Your posts are moderated
Related Questions
A coil of inductance 318.3mH and negligible resistance is linked in series with a 200 resistor to a 240V, 50Hz supply.  Calculate (a) The inductive reactance of the coil,

Q . Figure shows across (b)What is the answer if there is no outer covering of the pipe? Answer Reflection, r max = 90 0 -i=90 0 -59 0 =310     Let, i max  b

Define the Momentum and Impulse. Momentum, p, is a measure of a car's motion.   p =  m  v where p is momentum in kg-m/s, m is mass in kilograms and v is the velocity of the ca

Two elements A and B form compounds having molecular formulae AB 2 and AB 4 . dissolved in 2O g of benzene, 1 g of AB2 lower the freezing point by 2.3 K, whereas 1 g of AB4 lowers

calour formed in pure and impure spectrum

A 77.0-kg woman is walking 0.10 m/s east in the gym. A man throws a 15.0-kg ball south and accidentally hits the woman. The woman and the ball move together with a velocity

Described the two fundamental purpose of surveying?

Question 1. Discuss the physical characteristics of an X-ray beam. Write a note on factors influencing the quality and intensity of the X-ray beam 2. Explain the constructio

A light horizontal bar has a length of 3m. If a 102-kg mass is placed 80 cm away from the left end of the bar and a 109-kg mass is placed 2.15 m from the left end, where must it be