(B) We consider the vertical motion of the ball.Initial vertical velocity: $u_y = u \sin \theta = 20 \times \sin 30^{\circ} = 20 \times \frac{1}{2} =

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

(B) We consider the vertical motion of the ball.Initial vertical velocity: $u_y = u \sin \theta = 20 \times \sin 30^{\circ} = 20 \times \frac{1}{2} = 10 \,m/s$.Vertical acceleration: $a_y = -g = -10 \,m/s^2$.Time taken to reach the ground: $t = 3 \,s$.Using the equation of motion for vertical displacement: $s_y = u_y t + \frac{1}{2} a_y t^2$.Here, the displacement $s_y = -h$ (where $h$ is the height of the building).$-h = (10)(3) + \frac{1}{2}(-10)(3)^2$.$-h = 30 - 5(9) = 30 - 45 = -15 \,m$.Therefore, $h = 15 \,m$.

Class 11 Physics 3-2.Motion in Plane Projectile Motion from Hight

Easy

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal and with an initial speed of $20 \,m/s$. If the ball strikes the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $g = 10 \,m/s^2$) (in $\,m$)

AP EAMCET 2022 All AP EAMCET

A
$10$
B
$15$
C
$20$
D
$25$

Explore More

Browse All

Question Bank

All Subjects

Class 11 Questions

Class 11

Physics Questions

Chapter

3-2.Motion in Plane

Subtopic

Projectile Motion from Hight

Previous Year

AP EAMCET 2022 Paper All AP EAMCET years →

An aeroplane moving horizontally at a speed of $200 \; m/s$ and at a height of $8 \; km$ is to drop a bomb on a target. At what horizontal distance from the target should the bomb be released? (Take $g = 9.8 \; m/s^2$)

Medium

View Solution

$A$ bomber plane moves horizontally with a speed of $500\,m/s$ and a bomb released from it,strikes the ground in $10\,s$. The angle with the horizontal at which it strikes the ground will be $(g = 10\,m/s^2)$.

Medium

View Solution

From a tower of height $h$,one ball is thrown downwards with a velocity $u$ and another ball is thrown horizontally with the same velocity $u$. What is the ratio of their velocities when they reach the ground?

Medium

View Solution

$A$ particle is dropped from a height of $20\,m$ onto horizontal ground. There is wind blowing,due to which the horizontal acceleration of the particle becomes $6\,ms^{-2}$. Find the horizontal displacement of the particle until it reaches the ground (in $m$).

Medium

View Solution

$A$ ball is thrown from a rooftop at an angle of $45^\circ$ above the horizontal. It hits the ground a few seconds later. At what point during its motion does the ball have $(a)$ greatest speed, $(b)$ smallest speed, and $(c)$ greatest acceleration? Explain.

Medium

View Solution

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial

For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free

For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal and with an initial speed of $20 \,m/s$. If the ball strikes the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $g = 10 \,m/s^2$) (in $\,m$)

Similar Questions

An aeroplane moving horizontally at a speed of $200 \; m/s$ and at a height of $8 \; km$ is to drop a bomb on a target. At what horizontal distance from the target should the bomb be released? (Take $g = 9.8 \; m/s^2$)

$A$ bomber plane moves horizontally with a speed of $500\,m/s$ and a bomb released from it,strikes the ground in $10\,s$. The angle with the horizontal at which it strikes the ground will be $(g = 10\,m/s^2)$.

From a tower of height $h$,one ball is thrown downwards with a velocity $u$ and another ball is thrown horizontally with the same velocity $u$. What is the ratio of their velocities when they reach the ground?

$A$ particle is dropped from a height of $20\,m$ onto horizontal ground. There is wind blowing,due to which the horizontal acceleration of the particle becomes $6\,ms^{-2}$. Find the horizontal displacement of the particle until it reaches the ground (in $m$).

$A$ ball is thrown from a rooftop at an angle of $45^\circ$ above the horizontal. It hits the ground a few seconds later. At what point during its motion does the ball have $(a)$ greatest speed, $(b)$ smallest speed, and $(c)$ greatest acceleration? Explain.

Vedclass Test Series

Exam Paper Generator

Online Exam Module