A metal wire has a resistance of 13.00 at a temperature of 25.0 degree celsius

A race car starting from rest accelerates uniformly at a rate of 4.90 meters per squared. What is the cars speed after it has tr

shusha [124]

Ok, we need to find a relation for the speed as it relates to the acceleration. This is given by the integral of acceleration:

$v= \int\limits^{t}_{0} {a} \, dt' =at$

Where we have the initial velocity is 0m/s and a will be 4.90m/s².

But we see there is an issue now... We know the velocity as a function of time, but we don't know how long the car has been accelerating! We need to calculate this time by now finding the position function as a function of time. This way we can solve for the time, t, that it takes to go 200m accelerating this way and then substitute that time into our velocity equation and get the velocity.
Position is just the integral of velocity:

$s= \int\limits^{}_{} {at} \, dt = \frac{1}{2}at^2$

Where the initial velocity and initial position are both zero.

Now we set this position function equal to 200m and find the time, t, it took to get there

$\frac{1}{2}(a \frac{m}{s^2} )t^2=200m \\ \\ \frac{1}{2}4.90 \frac{m}{s^2} t^2=200m \\ \\ t^2= \frac{400m}{4.90 \frac{m}{s^2}}=81.63s^2 \\ \\ t= \sqrt{81.63s^2 } =9.04s$

Now let's put t=9.04s into our velocity equation:

$v =at=4.9\frac{m}{s^2} \times 9.04s=44.3 \frac{m}{s}$

8 0

3 years ago

A 9-μC positive point charge is located at the origin and a 6 μC positive point charge is located at x = 0.00 m, y = 1.0 m. Find

sukhopar [10]

Answer:

The coordinates of the point is (0,0.55).

Explanation:

Given that,

First charge $q_{1}=9\times10^{-6}\ C$ at origin

Second charge $q_{2}=6\times10^{-6}\ C$

Second charge at point P = (0,1)

We assume that,

The net electric field between the charges is zero at mid point.

Using formula of electric field

$E=\dfrac{kq}{r^2}$

$0=\dfrac{k\times9\times10^{-6}}{d^2}+\dfrac{k\times6\times10^{-6}}{(1-d)^2}$

$\dfrac{(1-d)}{d}=\sqrt{\dfrac{6}{9}}$

$\dfrac{1}{d}=\dfrac{\sqrt{6}}{3}+1$

$\dfrac{1}{d}=1.82$

$d=\dfrac{1}{1.82}$

$d=0.55\ m$

Hence, The coordinates of the point is (0,0.55).

3 0

3 years ago

2. A 200.0-kg bear grasping a vertical tree slides down at constant velocity. What is the friction force between the tree and th

Neporo4naja [7]

Answer: 1960 N

Explanation:

The bear is sliding down at constant velocity: this means that its acceleration is zero, so the net force is also zero, according to Newton's second law:

$F_{net}=ma=0$

There are two forces acting on the bear: its weight W, pulling downward, and the frictional force Ff, pulling upward. Therefore, the net force is given by the difference between the two forces:

$F_{net}=W-F_f=0$

From the previous equation, we find that the frictional force is equal to the weight of the bear:

$F_f=W=mg=(200.0 kg)(9.8 m/s^2)=1960 N$

8 0

3 years ago

What should you do if...

Hunter-Best [27]

Answer:

3. you need to ask your available lab instructors what to do.

4. You immediately have to drop down your cloth and roll it to extinguish the fire or move to the emergency shower if available

5. You have too keep calm and report to the lab instructor but do no shout.

6. Move immediately to the eye rinse basin if available and wash your eyes gently and thoroughly

6 0

3 years ago

What is photosynthesis

MA_775_DIABLO [31]

Answer:

The process

Explanation:

the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct.

6 0

3 years ago

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