# Tagged Questions

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### addition of a component of a vector to the same vector [on hold]

I am having a problem in the last part of this question-(D).My book says that it is not meaningful. I think that supposing a vector for instance 2i^ has a component 2i^. so when they are added it is ...
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### Finding resultant and direction of resultant

In this question- A motorboat is racing towards north at 25km/h and the water current in that region is 10km/hr in the direction of 60 degree east of south. Find the resultant velocity of the ...
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### A particle has $\overrightarrow{r}(0)=4m(\hspace{2pt}\hat{j}\hspace{2pt})$ and $\overrightarrow{v}(0)=(2m/s^2)\hat{i}$ [closed]

I am having trouble with these problems, and I want to gain a understanding of how to solve these. I'll put what I have tried at the end, even though I don't think it'll be of help. A particle has ...
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### Average acceleration when more than two different velocities occur [closed]

Suppose a car travels at 5m/s north for 5 seconds, it then turn east and travel at 7m/s for 10 seconds, finally it turns north east and travel at 10 m/s for 20 seconds. What is the average ...
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### How are the angles equal?

At the back of my mind I know they should be equal, but mathematically, how are the two $\Delta \phi$ angles equal? The only explanation present in the text is that, "both velocities are ...
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### Isn't this statement regarding projectile motion wrong?

Isn't this statement regarding projectile motion wrong? If a body is thrown at an angle to the horizontal with initial velocity $u$, then displacement of body as a function of time is ...
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### Kinematics simple question [closed]

Question: In order to protect himself from the rain, a person is standing holding an umbrella at right angle to the horizontal surface. The rain is falling at 10m/s when the velocity of the wind is ...
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### Contradiction of a scalar product

Can anyone resolve this contradiction: ...
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### Compute the minimal distance between two points in movement

There are two points, $A$ and $B$ that move according to these laws: $$\vec{x_a}= 20 -10 t$$ $$\vec{x_b}= -15 +15 t$$ $A$ moves along the x axis, $B$ along the y axis. I have to compute the ...
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### Understanding vectors in an example

I just read an example of vectors in my book which is confusing me. Three particles A,B and C are at the vertices of an equilateral trinagle ABC. Each of the particle moves with constant speed v. ...
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### Relative motion and how to calculate magnitude and velocity of objects relative to different given objects [closed]

A canoe has a velocity of 0.550m/s southeast relative to the earth. The canoe is on a river that is flowing at 0.540m/s east relative to the earth. Alright so I attempted many different things an ...
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### How do I meaningfully divide by a vector?

How long does it take a baseball with velocity $(30, 20, 25) m/s$ to travel from location $r_1 = (3, 7,−9) m$ to location $r_2 = (18, 17, 3.5)m$? I am thinking that it should be the ...
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### How does this shell hit the aircraft?

A fighter aircraft is flying horizontally at an altitude of 1500m with speed of 200m/s. The aircraft passes directly overhead an anti-aircraft gun. The muzzle speed of the gun is 600m/s. ...
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### Is it incorrect to explain the direction of a coded vector quantity?

For example, let's say that in a linear physics problem, all the data are given to a certain direction, and coded positively for direction to the right. So +5m/s would be a velocity of 5m/s to the ...
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### Vectors and motion in a plane [closed]

A particle travels with speed $50 m/s$ from the point $(3,-7)$ in the direction $7i-24j$ . Find its positional vector after 3 seconds. My approach: It has travelled a distance of 150m in the ...
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### Relative Velocity problem

I was solving many problems on relative velocity and observed that when the question asks, "what is the minimum time taken by the boat/man to cross the river.?" so the solution says that he ...
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### Utilizing maximum acceleration $a$ for displacement $d$ with initial velocity $v_0$ and final velocity $v_1$

Problem My goal is to move an object from point a to b (displacement $d$) as fast as possible utilizing the maximum available acceleration $a_{max}$, taking into account the initial velocity $v_0$ ...
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### Sign of acceleration

I'm developing an application using accelerometer sensor. I'm not good at physics so forgive me if the question is trivial. If I have 3 values of acceleration: $x$, $y$, $z$, I find acceleration ...
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### Is it necessary to know initial y velocity to solve this projectile motion problem?

A marble is launched horizontally off a 93.0-cm high table causing the marble to land on the floor 1.85 m from the base of the table. a.) How long was the ball in the air? b.) With what ...
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### Solving inclined plane using diff. frame

I was trying to solve frictionless inclined plane problem using a diff. frame as shown in the figure, and can't figure out that acceleration along the plane = g.sin(Θ), but I think it should be = ...
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### 2D - Kinematics - Linkage System using Vector Algebra [closed]

I have this question that I dont know how to solve correctly : My question is, how do I find $V_B$ ? I will find the angular velocities myself, but I want to know the method to get $V_B$ ? I know ...
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### Find vector position in time give this graph?

Graph is position x position. There are 3 points, $A$, $B$ and $C$. $A(0,2)$ $B(4,2)$ $C(6,0)$ Particle travels from $A$ to $B$ and from $B$ to $C$ at constant $v = 2 ~m/s$. Find vector ...