Tagged Questions

49 views

What is the value of $g$ at centre? [duplicate]

What is the value of $g$ at the centre of the Earth? Is it zero or infinity? My attempt: I know it's zero but applying law made me on fused.
40 views

What will be the acceleration of an object $A$ when its released by another object $B$ moving with an upward acceleration $a$?

What will be the acceleration of an object $A$ when its released by another object $B$ moving with an upward acceleration $a$? Will the acceleration of the object $A$ be more than the acceleration due ...
16 views

Is acceleration quadratic or linear outside of a gravity field? [duplicate]

So as I understand it: If you hit a wall at twice the speed you hit four times as hard? I often ask people this and everyone says "at twice the speed you hit twice as hard". $K=\frac{1}{2}mv^2$ is ...
45 views

Bomb trajectory from an airplane

If a plane is flying at a constant speed at some altitude like 5-6 km and it releases a bomb: does the bomb move forward at the same horizontal speed as the airplane? or does its horizontal speed ...
106 views

What does an applied force on an already accelerating object do?

I'm a big beginner having only taken Grade 11 high-school physics. Imagine this situation: an object is accelerating north, and while it's accelerating, it's 'hit' by a northward force. To me it ...
3k views

Why do heavier objects fall faster in air?

We all know that in an idealised world all objects accelerate at the same rate when dropped regardless of their mass. We also know that in reality (or more accurately, in air) a lead feather falls ...
131 views

261 views

If kinetic energy is a function of the square of velocity, how can gravitiational acceleration be constant?

Kinetic energy is defined as: $$E_k = \frac{mv^2}{2}$$ Because of the squared velocity term in there, the faster you're going, the more energy it takes to further ...
722 views

Integrating radial free fall in Newtonian gravity

I thought this would be a simple question, but I'm having trouble figuring it out. Not a homework assignment btw. I am a physics student and am just genuinely interested in physics problems involving ...
244 views

Change in speed of a satellite

Suppose there's some satellite orbiting the earth in circular motion. Suppose there's an asteroid that hits the satellite in the same direction as the instant velocity vector of the satellite. The ...
180 views

Where are we : On level ground or on a ramp - moving in a train?

Let's say we are traveling in a train. The path has two parts: one at ground-level and the other moving up on the ramp. The ramp has an inclination of $\arctan\frac{a}{g}$ with the horizontal, where ...
834 views

Slinky base does not immediately fall due to gravity

Why does the base of this slinky not fall immediately to gravity. My guess is tension in the springs is a force > mass*gravity but even then it is dumbfounding.
182 views

How is space ship's acceleration perceived if the acceleration is perpendicular to the velocity?

Spacecraft in orbit around the Earth are constantly accelerated by the gravitational field of Earth. That's why the spacecraft ($m \ll M$) is in an (elliptical) orbit around the centre of gravity of ...
372 views

Gravity and free fall

In Wikipedia it's stated that "[..] gravity, is the natural phenomenon by which physical bodies appear to attract each other with a force proportional to their masses". Then I found many examples ...
103 views

Gravity question [duplicate]

Possible Duplicate: Donâ€™t heavier objects actually fall faster because they exert their own gravity? When true: The force pulling the "heavy" object down is greater BUT it also takes more ...
4k views

Acceleration of two falling objects with identical form and air drag but different masses

I have a theoretical question that has been bugging me and my peers for weeks now - and we have yet to settle on a concrete answer. Imagine two balloons, one is filled with air, one with concrete. ...
2k views

Is acceleration due to gravity constant?

I was taught in school that acceleration due to gravity is constant. But recently, when I checked Physics textbook, I noted that $$F = \dfrac{G \cdot m_1 \cdot m_2}{r^2}$$ So, as the body falls ...
267 views

How to send a spacecraft to the moon without any acceleration

I have two (maybe equal) question 1- Is this possible to send a spacecraft to the moon without any acceleration(Constant speed)? 2-Is this possible to throw a ball on the top of tree without any ...
1k views

Questions from elevator ride

I like to play inside the lift (elevator). For instance, there are bars attached at the side of the lift, and I like to hold my body up using my two hands on the bar. I realised that I actually feel ...
2k views

Why Gravity attracts all objects with the same speed?

Why Gravity attracts all objects with the same speed? Is this question was solved? What is the exact answer?
676 views

When we throw an object in the presence of gravitational attraction is the mass of the object proportional to the time of fall or not?

I was confused when i saw two object of different masses (A and B)falling from the same height(h) but both of them strikes the ground at same time. Is this possible, that masses of the objects are ...
250 views

Accelerating elevator?

If your in an elevator accelerating downwards faster than gravity, would you be pushed up to the ceiling? Since gravity cannot match the acceleration of the elevator, you're wouldn't be able to move ...
523 views

How do we explain accelerated motion in Newtonian physics and in modern physics?

Maybe my question will seem stupid, but I am not a physicist so I have some problems understanding a classic Newtonian experiment: in the bucket experiment, why does he have to introduce the absolute ...
3k views

Why do two bodies of different masses fall at the same rate (in the absence of air resistance)?

I'm far from being a physics expert and figured this would be a good place to ask a beginner question that has been confusing me for some time. According to Galileo, two bodies of different masses, ...