Defence Exam  >  Defence Questions  >  A bullet is fired vertically up from a 400 m ... Start Learning for Free
A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will be
  • a)
    8 s
  • b)
    16 s
  • c)
    20 s
  • d)
    24 s
Correct answer is option 'C'. Can you explain this answer?
Verified Answer
A bullet is fired vertically up from a 400 m tall tower with a speed 8...
Total time taken to reach the ground T = t1+t2 +t3 u=80m/s

Velocity of the bullet at point A ,
 
VA=0m/s.
a=- lOm/s
V = u + at
0 = 80-10 t1 = 8s
t2 = t1 (as there is no air resistance)
Calculation for t3
Velocity of the bullet at point B,
VB = u=80m/s
h =400m

Time cannot be negative hence neglecting t3 = - 20s
Total time T= 8 + 8 + 4 = 20 s
View all questions of this test
Most Upvoted Answer
A bullet is fired vertically up from a 400 m tall tower with a speed 8...

Given data:
- Initial speed of the bullet, u = 80 m/s
- Height of the tower, h = 400 m
- Acceleration due to gravity, g = 10 m/s^2

Calculating time taken by the bullet to reach the ground:
- The time taken by the bullet to reach the ground can be calculated using the formula:
h = ut + (1/2)gt^2
- Substituting the values:
400 = 80t - (1/2)(10)t^2
- Simplifying the equation:
400 = 80t - 5t^2
5t^2 - 80t + 400 = 0
t^2 - 16t + 80 = 0
- Solving the quadratic equation, we get:
t = 20 sec

Therefore, the time taken by the bullet to reach the ground is 20 seconds. Hence, the correct answer is option 'c'.
Explore Courses for Defence exam

Similar Defence Doubts

A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer?
Question Description
A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? for Defence 2024 is part of Defence preparation. The Question and answers have been prepared according to the Defence exam syllabus. Information about A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for Defence 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer?.
Solutions for A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for Defence. Download more important topics, notes, lectures and mock test series for Defence Exam by signing up for free.
Here you can find the meaning of A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer?, a detailed solution for A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? has been provided alongside types of A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A bullet is fired vertically up from a 400 m tall tower with a speed 80 m/s. If g is taken as 10 m/s2, the time taken by the bullet to reach the ground will bea)8 sb)16 sc)20 sd)24 sCorrect answer is option 'C'. Can you explain this answer? tests, examples and also practice Defence tests.
Explore Courses for Defence exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev