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2 years ago

8

A particle of mas 0.1 kg moves along the trajectory x(t)-3t t where x is in meters and t is in seconds. What is the kinetic ener

gy of the particle at time t? Select one: a. 0.3 (t 1)3 o b. 0.25 (t2 -1) c. 0.25 (t + 1)2 d. 0.45 (t2+1)2 o e. 3.0 (1-)

1 answer:

devlian [24]2 years ago

6 0

Answer:

Kinetic energy = 0.45 joules

Explanation:

We have velocity of the particle is

$v=\frac{dx(t)}{dt}\\\\v=\frac{d(3t)}{dt}\\v=3m/s$

Now kinetic energy(K.E) is given by

$K.E=\frac{1}{2}mv^{2}$

applying values we get

Kinetic energy = $\frac{1}{2}0.1\times 3^{2}\\\\\therefore K.E=0.45Joules$

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2 years ago

In which case does viscosity play a dominant role? Case A: a typical bacterium (size ~ 1 mm1 mm and velocity ~ 20 mm/s20 mm/s) i

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Answer:

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Explanation:

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$F = \eta \times 10^{-6}\times 20\times 10^{-3}$

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from the above force calculation

In case B inertial force that represent mass is more than the inertial force in case of bacteria.

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3 years ago

Describe a technology used in space exploration.

Alex777 [14]

Answer:

High speed optical communication technology

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3 years ago

What is the electric potential energy of an electron at the negative end of the cable, relative to the positive end of the cable

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Answer:

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In this problem, we know that:

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$V_+=0V$

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$\Delta U = (-1.6\cdot 10^{-19})(-12)=1.92\cdot 10^{-18}J$

This means that the electron when it is at the negative terminal has $1.92\cdot 10^{-18}J$ of energy more than when it is at the positive terminal.

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3 years ago

A proton moving at 3.90 106 m/s through a magnetic field of magnitude 1.80 T experiences a magnetic force of magnitude 7.20 10-1

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Answer:

$\theta=40^0$

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