A ball thrown vertically upwards with a speed of 19.6 ms-1 from the to

1.	A ball thrown vertically upwards with a speed of 19.6 ms-1 from the top of a tower returns to earth in 6 sCalculate the height of the tower
Answer» u = 19.5 m/s t = 5 sec g = 9.8 m/s² Total distance covered while going up = S total distance covered while coming down = h+S At topmost point v = 0 v = u - gt 0 = 19.5 - 10 (9.8) t = 2 sec (appx) Now, The velocity of ball when it falls down a distance S after reaching topmost height (h+S) will be same as initial velocity (calculate yourself), and the time taken will again be 2 sec. So, total time elapsed = time for going up S + time for coming down S = 2+2 = 4 sec Total time = 5 sec Remaining time = 5-4 = 1 sec here u = 19.5 m/s(downwards) , t = 1 sec h = ut + 1/2 g t² h = 19.5 (1) + 1/2 (9.8) (1) = 19.5 + 4.9 = 24.4 m thankyou

A ball thrown vertically upwards with a speed of 19.6 ms-1 from the top of a tower returns to earth in 6 sCalculate the height of the tower

Answer»

u = 19.5 m/s

t = 5 sec

g = 9.8 m/s²

Total distance covered while going up = S

total distance covered while coming down = h+S

At topmost point

v = 0

v = u - gt

0 = 19.5 - 10 (9.8)

t = 2 sec (appx)

Now,

The velocity of ball when it falls down a distance S after reaching topmost height (h+S) will be same as initial velocity (calculate yourself), and the time taken will again be 2 sec.

So, total time elapsed = time for going up S + time for coming down S = 2+2 = 4 sec

Total time = 5 sec

Remaining time = 5-4 = 1 sec

here u = 19.5 m/s(downwards) , t = 1 sec

h = ut + 1/2 g t²

h = 19.5 (1) + 1/2 (9.8) (1) = 19.5 + 4.9 = 24.4 m

thankyou

Discussion

No Comment Found

Related InterviewSolutions

7. A body has a weight 50 N in air. Afterimmersing completely in liquid its weight is20 N. Then, the buoyant force on the bodywill be
Name the particulate which causes the disease mentioned below:(a)minamata (b)silicosis.
- Where does a body weight more at the surface of the carth or in a mine?
DelyAbody79entire chainthe ch.57. A body of mass 50gm collides elastically with anotherbody of mass 30 gm at rest. Then the percentage lossof the velocity of the colliding body during collision is1) 25% 2) 75% 3) 50% 4) 67%3) 120380.beide
What will be the acceleration of a body of mass5 kg if a force of 200 N is applied on it?
Rig. 5.168.13 Two bodles of masses 10 kg and 20 kg respectively kept on a smooth, hortzontalsurface are tied to the ends of a light string a horizontal force F 600 Nsapplied to lu A (t) B along the direction of string. What is the tension in thestring in each case
culate the gravitational force befween two protons kept at a distance67 x 10-27 kg. (1 femtometre = 10-15 m)
15. A uniform chain of length 2 m is kept on atable such that a length of 60 cm hangs freelyfrom the edge of the table. The total mass ofthe chain is 4 kg. What is the work done inpulling the entire chain onto the table ?(g = 10 m/s)1) 7.2J273.63) 120J4) 1200
Two block of mass 3 kg and 6 kg respectively are placed on a smooth 1.0 m/shorizontal surface. They are connected by a light spring of force 3 kgconstant k 200 N/m. Initially the spring is unstretched. The indicatedzmvelocities are imparted to the blocks. The maximum extension of thespring will be:A30 cm(C) 20 cm2.0 mls(B) 25 cm(D) 15 cm
88. A piece of stone is thrown vertically upwards. It reaches the maximum height in 3 seconds. If the accelerationof the stone be 9.8 m/s directed towards the ground, calculate the initial velocity of the stone with which itis thrown upwards.