Projectile Motion Help: Calculating Direction of a Ball Thrown from a Cliff

naimagul
Messages
10
Reaction score
0

Homework Statement


a ball is throwm horizontally from top of a cliff with velocity 10meter per second. height of cliff above the ground is 45 meters. calculate the direction of ball to horizontal surface just before it hits the grouND

The Attempt at a Solution

i found time=3s...and horizontal distance as 20m...but i cud not figure out ANYTHING ABT THE DIRECTION...PLZ HELP
 
Physics news on Phys.org
Do you know how to get the vertical and horizontal components of the ball's velocity right before it hits the ground? If so, you can directly use trigonometry to get the direction.
 
um i have tried a lot... can u please help me find the angle just before the angle hits the horizontal surface...m a learner...looking forward to ur cooperation
 
Gravity acts downwards, so it can't change the ball's horizontal speed. It's still 10 m/s on impact. As for vertical speed, can you find a kinematic equation that relates acceleration, distance traveled, initial speed, and final speed?
 
ideasrule said:
Gravity acts downwards, so it can't change the ball's horizontal speed. It's still 10 m/s on impact. As for vertical speed, can you find a kinematic equation that relates acceleration, distance traveled, initial speed, and final speed?

yes v²-u²=2as...where a is acceleration
u is initial velocity...s is distance...v is final velocity
 

Thread 'Initial conditions for orbits around a wormhole'

Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
View full post »

Thread 'Help to convert units of a simple formula'

The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?
View full post »

Similar threads

Solving a Ball Thrown off a Cliff: How Long Does it Take?
Replies
4
Views
2K
Find the height of a lamp based on the velocities of projectiles
Replies
40
Views
2K
How Far Can Water Spray from a Pipe Hole at a 45 Degree Angle?
Replies
1
Views
3K
Trajectory of a projectile from a cliff
Replies
1
Views
3K
Projectile Motion from a height with Air Resistance
Replies
1
Views
2K
Solving a 2D Projectile Motion Problem: Find x
Replies
3
Views
2K
Ball launched from a height of 5 meters --- Projectile motion
Replies
12
Views
1K
How Do You Solve Projectile Motion for a Car Driving Off a Cliff?
Replies
4
Views
2K
Find final velocity in a horizontal projectile motion
Replies
2
Views
4K
Projectile thrown horizontally off a cliff
Replies
22
Views
4K

Hot Threads

Recent Insights

Back
Top