# How to Solve a Kinematics Equation for a Dropped Ball from a Balloon?

In summary, the conversation involves a problem where a ball is dropped from a balloon at a height of 60 m while the balloon is moving at a speed of 7 m/s. The problem asks for the time it takes for the ball to reach the ground, with given values for initial velocity and acceleration. The solution involves setting up an equation and solving it, which may involve using the quadratic formula. It is suggested to simply solve the equation and not overthink the process. Additionally, it is recommended to read and save similar threads for further learning.

## Homework Statement

A ball is dropped from a balloon going up at a speed of
7 m/s. If the balloon was at a height 60 m at the time
of dropping the ball, how long will the ball take in
reaching the ground ?

## Homework Equations

u = –7 m/s, s = 60 m, a = g = 10 m/s^2

## The Attempt at a Solution

i tried solving it by using D=ut+1/2at^2
n got stuck wit this 5t^2+7t-60=0
can anyone tell me a simpler say to solve this equation?

## Homework Equations

u = –7 m/s, s = 60 m, a = g = 10 m/s^2

## The Attempt at a Solution

i tried solving it by using D=ut+1/2at^2
n got stuck wit this 5t^2+7t-60=0
can anyone tell me a simpler say to solve this equation?
You are nearly done with finding the solution. Remember that u is -7m/s, not +7m/s.

Are you familiar with the quadratic formula? Use that and you'll have t.

DO NOT THINK THERE IS ALWAYS A SIMPLER WAY!

See, you first made the equations. Was there any complicated part involved over there? No! There was no imagination, no setting up, no interpretation required.

So the problem itself was very simple.

Now, AS A PART OF THE PROBLEM, you have to solve a quadratic equation.

Don't give this part too much importance in your mind. Tell yourself - yeh aa gaya toh answer mil gaya. So, mindlessly, solve the quadratic equation. THAT's IT.

Set up an equation and solve it - ismein kuchh aur simple ho hi nahin sakta!

Keep posting more and more questions dude - we have a lot to work on! And whenever someone tells you something here - think over it and also make a note of it in your notebook or something.

At the end of a month or so - you should have the collective intelligence of all the contributors on physics forums. Sab ka experience tujhe muft main mil raha hai!

ALSO - DO YOURSELF A FAVOUR:

* At the bottom of the page - you have "similar threads for post title", right? Read all of them one by one, and save a copy on your hard disc as a PDF (Use A PDF printing tool like CutePDF or something.).

Its a nice way to learn - listening to the doubts of others and understanding how they had been solved. Again, at the end of the month, you should have around 500 PDFs on your hard disc if you are regular here!

## 1. What is rest and motion kinematics?

Rest and motion kinematics is the study of the movement of objects and bodies in relation to time, position, velocity, and acceleration. It focuses on the mathematical description and analysis of motion in both stationary (rest) and moving (motion) reference frames.

## 2. What is the difference between rest and motion kinematics?

The main difference between rest and motion kinematics is that rest refers to the state of an object when it is not moving, while motion refers to the state of an object when it is changing its position over time. Rest and motion are two fundamental states of an object and are used to describe various types of motion, such as linear, rotational, and oscillatory motion.

## 3. What are the key concepts in rest and motion kinematics?

The key concepts in rest and motion kinematics include displacement, velocity, acceleration, time, and position. Displacement is the change in an object's position with respect to a reference point, while velocity is the rate of change of displacement over time. Acceleration is the rate of change of velocity over time, and time is the duration of an object's motion. Position refers to the location of an object in space at a specific time.

## 4. How does rest and motion kinematics relate to other branches of physics?

Rest and motion kinematics is closely related to other branches of physics, such as mechanics, dynamics, and kinematics. Mechanics deals with the study of the motion and behavior of physical objects, while dynamics focuses on the forces that cause motion. Kinematics is a subset of mechanics that specifically deals with the mathematical description and analysis of motion.

## 5. What are some real-world applications of rest and motion kinematics?

Rest and motion kinematics has numerous real-world applications, such as in engineering, robotics, and sports. It is used to design and analyze the motion of machines and structures, program robots to move and perform tasks, and understand the mechanics of human movement in sports. It is also used in the development of transportation systems, such as cars, airplanes, and spacecraft.

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