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3 years ago

Will mark as BRAINLIEST.......

Physics

2 answers:

Alborosie3 years ago

7 0

This is the written answers to find the velocity and acceleration of r

lubasha [3.4K]3 years ago

6 0

Answer:

We have the position vector given in terms of time t. r(t) = t^3*i + t^2*j

To find the velocity vector we have to differentiate r(t) with respect to time.

r'(t) = 3t^2*i + 2t*j

The vector representing acceleration is the derivative of the position vector

r''(t) = 6t*i + 2*j

When time t = 2.

The velocity vector is 3*2^2*i + 2*2*j

=> 12*i + 4*j

The speed is the absolute value of the velocity vector or sqrt(12^2 + 4^2) = sqrt (144 + 16) = sqrt 160

The acceleration vector is 6*2*i + 2*j

=> 12*i + 2*j

The required acceleration at t=2 is 12*i + 2*j and the speed is sqrt 160.

Explanation:

Can I have thx and brainliest?

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An electron, moving south, enters a uniform magnetic field. Because of this uniform magnetic field, the electron curves upward.

Flura [38]

Answer:

Towards the west

Explanation:

Magnetic force is the interaction between a moving charged particle and a magnetic field.

Magnetic force is given as

F = q (V × B)

Where F is the magnetic force

q is the charge

V is the velocity

B is the magnetic field

V×B means the cross product of the velocity and the magnetic field

NOTE:

i×i=j×j×k×k=0

i×j=k. j×i=-k

j×k=i. k×j=-i

k×i=j. i×k=-j

So, if the electron is moving southward, then, it implies that the velocity of it motion is southward, so the electron is in the positive z-direction

Also, the electron is curved upward due to the magnetic field, this implies that the force field is directed up in the positive y direction.

Then,

V = V•k

F = F•j

Then, apply the theorem

F •j = q ( V•k × B•x)

Let x be the unknown

From vector k×i =j.

This shows that x = i

Then, the magnetic field point in the direction of positive x axis, which is towards the west

You can as well use the Fleming right hand rule

The thumb represent force

The index finger represent velocity

The middle finger represent field

3 0

3 years ago

What is the formula for Impedance for circuit with R, C, and L?

NikAS [45]

Answer:

The formula for Impedance for circuit with R, C, and L are:

$z=\sqrt{R^{2}+\left ( \omega L-\frac{1}{\omega C} \right )^2}$

The impedance Z of the series RLC circuit depend upon angular frequency ω. Impedance is measured in ohms and resistance (R), inductance reactance and capacitive reactance. Series RLC circuit consist of the resistance, a capacitance and an inductance connected in the circuits. Electrical impedance is the measurement of the opposition that a circuit present in a current.

3 0

3 years ago

2. When pressing the accelerator on a

Marianna [84]

Answer: chemical; mechanical

8 0

4 years ago

A particle moves along the x-axis with velocity given by v(t)=3t2+6t for time tâ¥0. If the particle at position x=2 at time t=0,

sergey [27]

Answer:

b) 6

Explanation:

Given

v(t)=3t²+6t

X(0) = 2

X(1) = ?

Knowing that

v(t)=3t²+6t = dX/dt

⇒ ∫dX = ∫(3t²+6t)dt

⇒ X - X₀ = t³ + 3t²

⇒ X(t) = X₀ + t³ + 3t²

If X(0) = 2

⇒ X(0) = X₀ + (0)³ + 3(0)² = 2

⇒ X₀ = 2

then we have

X(t) = t³ + 3t² + 2

when

t = 1

X(1) = (1)³ + 3(1)² + 2

X(1) = 6

8 0

4 years ago

Read 2 more answers

A train starts from rest and accelerates uniformly, until it has traveled 5.6 km and acquired a velocity of 42 m/s. The train th

Rasek [7]

Answer:

0.1575 m/s^2

Explanation:

Solution:-

- Acceleration ( a ) is expressed as the rate of change of velocity ( v ).

- We are given that the trains starts from rest i.e the initial velocity ( vo ) is equal to 0. Then the train travels from reference point ( so = 0 ) to ( sf = 5.6 km ) from the reference.

- During the travel the train accelerated uniformly to a speed of ( vf =42 m/s ).

- We will employ the use of 3rd kinematic equation of motion valid for constant acceleration ( a ) as follows:

$v_f^2 = v_i^2 + 2*a*( s_f - s_o )$

- We will plug in the given parameters in the equation of motion given above:

$42^2 = 0^2 + 2*a* ( 5600 - 0 )\\\\1764 = 11,200*a\\\\a = \frac{1,764}{11,200} \\\\a = 0.1575 \frac{m}{s^2}$

Answer: the acceleration during the first 5.6 km of travel is 0.1575 m / s^2

7 0

3 years ago