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$\vec{F} = m\vec{a}$ means that an object with a force $\vec{F}$ exerted upon it accelerates by an amount $\vec{a}$, not that an object accelerating with $\vec{a}$ exerts a force $\vec{F}$ on something else. Typically, the force exerted by an object has nothing to do with Newton's second law, but is given by other laws (like Coulomb's law in electrostatics). ...


3

In your context, the second interpretation is correct. The fact is that falling objects accelerate both on Earth and on the Moon. The sentence is saying that the amount of this acceleration, regardless the source, is six times greater on Earth than on the Moon. In other words, things accelerate towards the surface of Earth six times faster than they ...


2

You can't extrapolate like this and the function may be neither linear nor logarithmic. The car is subject to frictional forces from air-resistance, rolling-resistance, gear-train resistance, resistive forces inside the engine and other resistive forces. Each of these depends not only on speed but also on other factors like shape, selected gear, engine RPM, ...


2

First We'll see the FBD (Free Body Diagram)and we get: Where Fc is normal force acting (Force of contact). From FBD of 5 Kg block (By newton's 2nd law) $$F-F_c = ma$$ (1) From FBD of 10 Kg block $$F_c=Ma$$ Solving above equations we will get: $$F=ma+Ma$$ $$a=F/(m+M)$$ Putting the values you may get your result and your resultant force.


2

The explanation comes from earlier in that paragraph: If all the co-ordinates and velocities are simultaneously specified, it is known from experience that the state of the system is completely determined and that its subsequent motion can, in principle, be calculated. This is just saying the familiar thing that if you know the laws of physics for the ...


2

Although an object that moves with constant velocity has no acceleration, it has kinetic energy and it has momentum. Acceleration is not a conserved quantity. It is not passed from one object to another. Momentum and energy, however, are conserved quantities that pass from one object to another. If a moving object hits a target, kinetic energy will be ...


2

Because the non-tangential component of the acceleration always points toward the concave side. This is a mathematical result, with the proofs given, but to provide physical intuiton consider the non-tangential component of acceleration. This component doesn't affect the magntitude of the velocity vector, but changes its direction in a circular fashion. ...


2

Cicero gave you the math; let me give you the picture. Looking at this: The blue blob is an object initially moving horizontally to the right. At point B I give it a push upwards; it will then follow a new trajectory. You probably have no difficulty determining that the mass had to accelerate vertically to get its new direction. Now make the steps ...


1

2 points: first, $F=ma$ describes the acceleration of an object due to the sum of all forces acting on the object. If these forces are in different directions, they may partly or fully cancel each other out. In the case where the object is not accelerating (so it's moving with constant speed in a constant direction, or it's not moving at all), the sum of ...


1

The definition of acceleration, $a = \frac{dv}{dt}$ is always correct, and any other equations of acceleration are derived from it, depending on the conditions. To use this equation, you need to have a basic understanding of calculus. For example: condition: constant acceleration. This means $\frac{dv}{dt}$ is constant. This means that $v = at + constant$ ...



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