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jek_recluse [69]
4 years ago
11

While standing on a bridge 40.0 m above the ground, you drop a stone from rest. when the stone has fallen 3.80 m, you throw a se

cond stone straight down. what initial velocity must you give the second stone if they are both to reach the ground at the same instant? take the downward direction to be the negative direction?
Physics
1 answer:
Norma-Jean [14]4 years ago
3 0
Given: distance 1 d₁ = 40 m;  distance 2 d₂ = 3.8 m   g = -9.8 m/s²

 Initial Velocity Vi = 0  Final Velocity of stone 2 is unknown = ?

Total distance dₓ = d₁ - d₂  = 40 m - 3.8 m = 36.2 m

Formula: a = Vf² -  Vi²/2d   derive for Final Velocity Vf
 
acceleration is now due to gravity, therefore a = g

Vf = √2gd   Vf = √2(9.8 m/s²)(36.2 m)

Vf = 26.64 m/s  

Reason: The second stone will still start from rest.


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A mass attached to the end of a spring is oscillating with a period of 2.25 s on a horizontal frictionless surface. The mass was
Rudiy27

Answer:

X=0.0389m

Explanation:

From the question we are told that:

Period of spring T_s=2.25s

Initial Position of Mass x=0.0480m

Final Mass period T_f=5.85s

Generally the equation for the Mass location is mathematically given by

X=xcos*\frac{2\pi T_s}{T_f}

X=0.048*cos*\frac{2\pi 5.85}{2.25}

X=0.0389m

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3 years ago
HELP PLEASE!! <br><br>what will happen if you add a stronger battery to an electromagnet?? <br><br>​
Gala2k [10]

The electromagnetic force will be stronger since the electromagnet get it's force from the battery.

6 0
4 years ago
What must the minimum tension of a single?
frozen [14]

Connexus Physics pre-ap semester A final exam, all correct answers. And y’all better be freaking grateful, because it took a long time to type all this out.

<span>1)      </span>In the steps of the scientific method…
A. Interpreting results

<span>2)      </span>The radius of the Earth is…
B. 6.37 x 10^3 km

<span>3)      </span>Which of the following equations best describes…
D. y = 1/2x

<span>4)      </span>In the graph, what is the correct description…
C. Negative position

<span>5)      </span>The motion of a ball on an inclined plane is described…
C. vi

<span>6)      </span>Acceleration due to gravity is also called
C. free-fall acceleration

<span>7)      </span>Which of the following is a physical quantity…
A. vector

<span>8)      </span>In a coordinate system, a vector is…
A. Cos (theta)

<span>9)      </span>Which of the following is an example of projectile motion?
B. a thrown baseball

<span>10)   </span>A newton is equivalent to which…
A. kg * m/s^2

<span>11)   </span>In the free-body diagram shown below, which of the following…
C. 4050 N

<span>12)   </span>A net force of 6.8 N accelerates a 31 kg scooter…
A. 0.22 m/s^2

<span>13)   </span>A change in the gravitational force acting…
C. Weight

<span>14)   </span>A passenger on a bus moving east sees a man standing on a curb…
C. move west at a speed that is equal to the bus’s speed.

<span>15)   </span>In which of the following scenarios is no net work done?
B. A car travels at a constant speed on a flat road.

<span>16)   </span>What is the kinetic energy of a 0.135 kg baseball thrown at 40.0 m/s?
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<span>17)   </span>Which of the following refers to the sum of kinetic energy…
D. mechanical energy

<span>18)   </span>Which of the following are not units of power?
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<span>20)   </span>Two skaters stand facing…
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<span>21)   </span>In an inelastic collision…
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6 0
3 years ago
Two positive point charges, each of which has a charge of 2.5 × 10−9 C, are located at y = + 0.50m and y = − 0.50m. Find the mag
nadya68 [22]

Answer:

F = 147,78*10⁻⁹ [N]

Explanation:

By symmetry the Fy components of the forces acting on charge in point x = 0,7 m canceled each other, and the total force will be twice Fx ( Fx is x axis component of one of the forces .

The angle β  ( angle between the line running through one of the charges in y axis and the charge in x axis) is

tan β  =  0,5/0,7

tan β  = 0,7142    then   β = arctan 0,7142      ⇒   β = 35 ⁰

cos  β = 0,81

d = √ (0,5)²  +  (0,7)²       d1stance between charges

d = √0,25 + 0,49

d =  √0,74  m

d = 0,86  m

Now Foce between two charges  is:

F  = K* q₁*q₂/ d²      (1)

Where  K  = 9*10⁹ N*m²/C²

q₁  =  2,5* 10⁻⁹C

q₂  = 3,0*10⁻⁹C

d²  = 0,74 m²

Plugging these values in (1)

F  =  9*10⁹* 2,5* 10⁻⁹*3,0*10⁻⁹ / 0,74       [N*m²/C²]*C*C/m²

F = 91,21 * 10⁻⁹   [N]

And  Fx  =  F*cos  β

Fx  =  91,21 * 10⁻⁹ *0,81

Fx =73,89*10⁻⁹  [N]

Then total force acting on charge located at x = 0,7 m is:

F = 2* Fx

F = 2*73,89*10⁻⁹  [N]

F = 147,78*10⁻⁹ [N]

8 0
3 years ago
A force produces an acceleration of 5 ms
Dmitrij [34]

F = m • a (I. Newton)

F = (4 kg) x (5 m/s^2)

F = 20 Newtons

8 0
3 years ago
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