Why Can't I Use V = Vo + at to Calculate Time for a Car Falling Off a Cliff?

Click For Summary
SUMMARY

The discussion centers on the application of the equation V = Vo + at to calculate the time it takes for a car to reach a speed of 100 km/h after rolling off a vertical cliff. The initial velocity (Vo) is 0 m/s, and the acceleration (a) due to gravity is 9.8 m/s². However, this equation is not suitable for this scenario because it does not account for the vertical distance fallen, which is necessary to determine the time accurately. The correct approach involves using kinematic equations that incorporate both vertical displacement and time.

PREREQUISITES
  • Understanding of kinematic equations in physics
  • Knowledge of gravitational acceleration (9.8 m/s²)
  • Familiarity with units of speed (e.g., converting km/h to m/s)
  • Basic algebra skills for solving equations
NEXT STEPS
  • Study the kinematic equation x = Vo*t + 1/2at² for vertical motion
  • Learn how to convert speed from km/h to m/s for calculations
  • Explore the concept of free fall and its implications in physics
  • Review examples of projectile motion to understand vertical and horizontal components
USEFUL FOR

Students studying physics, educators teaching kinematics, and anyone interested in understanding the principles of motion under gravity.

Struggling
Messages
52
Reaction score
0
ok I've just cracked the ****s, for this question:

A car rolls gentley(Vo=0 m/s) off a vertical cliff. How long does it take for it to reach 100km/hr.

why can't i use V = Vo + at
where:

V= 100
Vo = 0
a = 9.8(gravity)
t = ?

the only equations I've been given to do this are:

V = Vo + at
V^2 = Vo^2 + 2ax
x=volt + 1/2at^2

ARGGGGGHHHHHHHHHHHHHHHHHH!
 
Physics news on Phys.org
Thats a good question, why can't you use it?
What did you get for an answer using it?
 
dont worry i got it, stupid me
 
Last edited:

Similar threads

Baseball in the air 2D motion question
  • · Replies 1 ·
Replies
1
Views
2K
How Do You Calculate the Meeting Point of Two Stones Thrown from a Cliff?
  • · Replies 1 ·
Replies
1
Views
2K
How Fast Was the Second Stone Thrown to Match the First at the Cliff Base?
  • · Replies 2 ·
Replies
2
Views
2K
Solving for Launch Angle Using Vo
  • · Replies 1 ·
Replies
1
Views
2K
How Long Does It Take to Fall from a Cliff?
  • · Replies 3 ·
Replies
3
Views
6K
How far does the police car travel to catch a speeder traveling at 180 km/hr?
  • · Replies 1 ·
Replies
1
Views
2K
How Far Will a Car Coast Up a Hill After Running Out of Gas?
  • · Replies 8 ·
Replies
8
Views
4K
I believe I can Fly~I believe I can touch the sky
  • · Replies 3 ·
Replies
3
Views
2K
Using Kinematics to find the Distance of an object dropped from rest
  • · Replies 1 ·
Replies
1
Views
3K
Calculate T for Maximum Altitude: 1D Kinematics Problem Solution
  • · Replies 5 ·
Replies
5
Views
4K