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3 years ago

What do you need to know to be able to determine how far a projectile travels horizontally?

1 answer:

5 0

As for me, there are two suitable answers for the question represented above and here is a short explanation why I consider these two to be correct :
D. The horizontal velocity of the projectile and B. The length of time before it lands
 $v_x = v*cos(x) [

d_x = v_x(t) + ½at²$ -- this led me to answers! Hope everything is clear! Regards!

You might be interested in

A 30 N rock falls from a 40 m cliff. At what point during its fall are its

vaieri [72.5K]

Answer:

Both energies are equal when the rock has fallen 20 m or equivalently when it is at a height of 20 m.

Explanation:

Potential and Kinetic Energy

The gravitational potential energy is the energy an object has due to its height above the ground. The formula is

$U=mgh$

Where:

m = mass of the object

g = acceleration of gravity (9.8~m/s^2)

h = height

Note we can also use the object's weight W=mg into the formula:

$U=Wh$

The kinetic energy is the energy an object has due to its speed:

$\displaystyle K=\frac{1}{2}mv^2$

Where v is the object's speed.

Initially, the object has no kinetic energy because it's assumed at rest.

The W=30 N rock falls from a height of h=40 m, thus:

$U=30*40=1,200 J$

Since the sum of the kinetic and potential energies is constant:

U' + K' = 1,200 J

Here, U' and K' are the energies at any point of the motion. Since both must be the same:

U' = K' = 600 J

U'=Wh'=600

Solving for h':

$\displaystyle h'=\frac{600}{W}=\frac{600}{30}=20~m$

Both energies are equal when the rock has fallen 20 m or equivalently when it is at a height of 20 m.

3 0

3 years ago

Two resistors connected in series have an equivalent resistance of 724.5 Ω, when they are connected in parallel, their equivalen

dybincka [34]

Answer:

544.65 ohm and 179.84 ohm

Explanation:

Hello

Let

Resistor 1 (R1) and Resistor 2 (R2)

in series $R_{eq} =R1+R2$

in parallel

$\frac{1}{R_{eqp} } =\frac{1}{R1} +\frac{1}{R2}\\\\R1=R_{eqs} -R2\\\\R1 =724.5-R2 (equation 1)\\ R_{eqp}}=\frac{R1*R2}{R1+R2}\\\\\ 135.2 = \frac{R1*R2}{R1+R2}(equation 2)\\\\\\\\replacing 1 in \ 2\\\\probema data$

$135.2=\frac{(724.5-R2)(R2)}{724.5-R2+R2} }\\135.2=\frac{(-R_{2} ^{2}+724.5R2) }{724.5}\\ 135.2*724.5=-R_{2} ^{2}+724.5R_{2}\\\\R_{2} ^{2} -724.5R_{2} +97952.4 =0\\R_{2} =\frac{724.5 \±\sqrt{(-724.5^{2})-4(1)(97952.4) } }{2(1)}\\R_{2} =\frac{724.5\±\sqrt{(133092.25) } }{2(1)}\\\\R_{2} =\frac{724.5+364.81810}{2} \\R_{2} =544.65 ohm\\\\R_{2} =\frac{724.5-364.81810}{2} =179.84 ohm$ \\\\

let R2=544.65 and replace in equation 1

R1=724.5-544.65

R1=179.85

so, the resistors are 544.65 ohm and 179.84 ohm

Have a great day

7 0

4 years ago

What force pulls the moon towards the earth?

yawa3891 [41]

Gravity pulls the moon towards the earth.

3 0

3 years ago

As an aid in working this problem, consult concept simulation 5.2. car a uses tires for which the coefficient of static friction

4vir4ik [10]

The speed for a curve of a given radius is proportional to the square root of the coefficient of static friction. The allowed speed in the second curve is about
(20 m/s)√(0.7/1.1) ≈ 15.95 m/s

7 0

3 years ago

True or False: If your gas pedal jams, you should turn the key to lock to lock the steering wheel.

Bond [772]

Answer:False

Explanation:

Turn the key to lock is not advisable as it lock the steering wheel and may create a dangerous situation.

Following steps can be taken in this situation

Try to press the brake to stop the vehicle
Shift gear to neutral in order to cease the acceleration of car.
Try to lift the gas pedal in order to decrease the velocity of car.

5 0

3 years ago

Read 2 more answers