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3 years ago

Calculate the speed of a bike rider who accelerates (from rest) for 5 seconds down a hill at an acceleration of 8

Physics

1 answer:

olya-2409 [2.1K]3 years ago

6 0

Answer:

speed=abs(v)=40ms^-1

Explanation:

acceleration, a = (v-u)/t

since initial velocity u=0 (at rest) and a=8ms^-2,

8=v/5

hence after 5 seconds, v=40ms^-1

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Nookie1986 [14]

Answer:

The answer is " $3.83 \times 10^9 \ m$ "

Explanation:

Z=2, so the equation is $E= \frac{-4B}{n^2}$

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The energy is the difference in transformation, name the energy delta E Deduct these two energies

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$\Delta E=2.18 \times 10^{-18} ( \frac{1}{4}- \frac{1}{81})$

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3 years ago

Calculate the kinetic energy of a 2.2kg brick when it has a speed of 4.9m/s

Alborosie

Answer:

Kinetic energy of the brick is 26.4 Joule

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3 years ago

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Calculate the work done by a 50.0 N force on an object as it moves 9.00 m, if the force is oriented at an angle of 135° from the

aivan3 [116]

Answer:

Work done, W = -318.19 Joules

Explanation:

It is given that,

Force acting on the object, F = 50 N

Distance covered by the force, d = 9 m

Angle between the force and the distance traveled, $\theta=135^{\circ}$

The work done by an object is equal to the product of force and distance traveled. It is equal to the dot product of force and the distance. Mathematically, it is given by :

$W=Fd\ cos\theta$

$W=50\times 9\times \ cos(135)$

W = -318.19 Joules

So, the work done by the force is 318.19 Joules. The work is done in opposite to the direction of motion. Hence, this is the required solution.

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3 years ago

LAST ONE NEED HELP.A car accelerates from rest to 20 m/s, in 5 seconds. The car exerts a force of 6000 N. What is the mass of th

Slav-nsk [51]

Answer:

1500kg

Explanation:

Initial velocity(u)=0m/s

Final velocity(v)=20m/s

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3 years ago