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3 years ago

12. A cross-country race car driver sets out on a 1.00 hour, 100.0 km race. At the halfway marker

Physics

1 answer:

Akimi4 [234]3 years ago

8 0

Answer:

A.) Time = 0.625 hrs = 37.5 minutes

B.) Speed required = 133.33km/hr

Explanation:

Given the following :

Total race distance = 100km

Total time required = 1 hour = 60 minutes

Average speed after traveling 50km = 80km/hr

80km/hr : This means it will take one hour to cover a distance of 80km

Therefore, time taken to cove first 50km at that average speed equals :

1 hour = 80 km

t hours = 50km

80t = 50

t = 50/80

t = 5/8 hours

t = 0.625hours

t = 0.625 * 60 = 37.5minutes

Average speed required to complete the race in 1 hour = 100km/hr

Time used to complete first 50km = 0.625 hour

Time remaining: (1 - 0.625) hour = 0.375

Speed required = Distance left / time left

Speed required = 50 / 0.375

Speed required = 133.33km/hr

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SIZIF [17.4K]

Answer:

The acceleration that the jet liner that must have is 2.241 meters per square second.

Explanation:

Let suppose that the jet liner accelerates uniformly. From statement we know the initial ( $v_{o}$ ) and final speeds ( $v_{f}$ ), measured in meters per second, of the aircraft and likewise the runway length ( $d$ ), measured in meters. The following kinematic equation is used to calculate the minimum acceleration needed ( $a$ ), measured in meters per square second:

$a = \frac{v_{f}^{2}-v_{o}^{2}}{2\cdot d}$

If we know that $v_{o} = 0\,\frac{m}{s}$ , $v_{f} = 82\,\frac{m}{s}$ and $d = 1500\,m$ , then the acceleration that the jet must have is:

$a = \frac{\left(82\,\frac{m}{s} \right)^{2}-\left(0\,\frac{m}{s} \right)^{2}}{2\cdot (1500\,m)}$

$a = 2.241\,\frac{m}{s^{2}}$

The acceleration that the jet liner that must have is 2.241 meters per square second.

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3 years ago

The mechanical advantage to simple machines is that they allow a decreased input force to create a larger output force. please s

Rina8888 [55]

<span>The mechanical advantage to simple machines is that they allow a decreased input force to create a larger output force.

<span>TRUE</span></span>

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3 years ago

5g of ammonium nitrate was dissolved in 60g of water in an insulated container. The temperature at the start of the reaction was

Minchanka [31]

Answer: The energy absorbed by the reaction from the water is 996 Joules.

Explanation:

Energy absorbed by the reaction or energy lost by the water to the reaction,Q.

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Specific heat of water = c = 4.15 J\g ^oC

Change is temperature= $\Delta T=19^oC-23^oC=-4^oC$

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Negative sigh indicates that energy was given by the water to the reaction.

The energy absorbed by the reaction from the water is 996 Joules.

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3 years ago

How will you join three resistances, each of 2 ohm so that the effective resistance is 3 ohm?

svet-max [94.6K]

First I will parallel two of the resistors, creating a net 1 ohm. Then I will series that with the remaining 2-ohm resistor, resulting in 3 ohms.

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3 years ago

Liquids take the shape of the bottom of their container, while gases take the shape of their entire container. The shape solids

motikmotik

Answer:

...

Explanation:

sigh its not that hard

Any liquid takes form of the shape of the container it goes into.

Gasses take the form of the whole thing because it spreads throughout it.

Solids are already a shape so it cant take the shape of the container if it already has one. yk

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3 years ago