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Darina [25.2K]
3 years ago
7

Sally and Ramona were competing in a four-lap, one-mile foot race. Sally’s style was to run at a constant rate of 12 mph. Ramona

decided to run her first three laps at 11 mph, and save a ‘kick’ in order to run a 16 mph pace for the fourth and final lap. Who wins the race, and by how many minutes or seconds?
Physics
1 answer:
svetoff [14.1K]3 years ago
7 0

Sally wins the race by 0.03 min

Explanation:

To find time = distance / velocity

Sally;

1 mile / 12 mph

= ¹/12 hrs * 60

= 5 min

Ramona;

³/4 mile ÷ 11 mph  +  ¹/4 mile ÷ 16 mph

= ³/44 hrs + ¹/64 hrs

= 4.09 min + 0.94 min

= 5.03 min

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Step-#1:

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Find the strength and direction of the magnetic field at P,

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Step #3:

Take the two sets of magnitude and direction that you wrote down

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3 years ago
A 50.0 Watt stereo emits sound waves isotropically at a wavelength of 0.700 meters. This stereo is stationary, but a person in a
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3 years ago
demonstrate in a brief paragraph how the search to explain planetary orbits exemplifies the scientific method and then use of mo
kari74 [83]

Answer:

People firstly believe that the planets move in a circular orbit until Newton came up with his hypothesis by inventing calculus so that we could understood and calculated planetary orbits and their accuracy.

Explanation:

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8 0
3 years ago
Cole is riding a sled with initial speed of 5 m/s from west to east. the frictional force of 50 n exists due west. the mass of t
stepan [7]
We can calculate the acceleration of Cole due to friction using Newton's second law of motion:
F=ma
where F=-50 N is the frictional force (with a negative sign, since the force acts against the direction of motion) and m=100 kg is the mass of Cole and the sled. By rearranging the equation, we find
a= \frac{F}{m}= \frac{-50 N}{100 kg}=-0.5 m/s^2

Now we can use the following formula to calculate the distance covered by Cole and the sled before stopping:
a= \frac{v_f^2-v_i^2}{2d}
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d is the distance covered

By rearranging the equation, we find d:
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3 0
3 years ago
Calculate the total energy of 4.0 kg object moving horizontally at 20 m/s 50 meters above the surface.
Serhud [2]

Answer:

Correct answer:  E total = 2,800 J

Explanation:

Given:

m = 4 kg   the mass of the object

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H = 50 m the height of the object above the surface

E total = ? J

The total energy of an object is equal to the sum of potential and kinetic energy

E total = Ep + Ek

Ep = m g H   we take g = 10 m/s²

Ep = 4 · 10 · 50 = 2,000 J

Ek = m V² / 2

Ek = 4 · 20² / 2 = 2 · 400 = 800 J

E total = 2,000 + 800 = 2,800 J

E total = 2,800 J

God is with you!!!

4 0
3 years ago
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