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4 years ago

A bicyclist is in a 50-km race. She says she had an average velocity of 35.

Physics

1 answer:

zlopas [31]4 years ago

8 0

The correct answer to this is (A. Units Only).

It shows that there is a velocity of 35, but the units are missing.

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The fundamental resolution of an optical instrument is set by __________.

inysia [295]

Answer:C . The wave nature of light.

Explanation: The wave nature of light has been described in the refraction and diffraction of light when it comes in contact with a prism.

Wave nature of light has been described through this equation C= velocity( measured in meters per second square), Wavelength (lambda) which is the distance between successive antinodes or nodes,it is measured in meters. and Frequency is the number of times light waves pass through a point in one second, usually measured in Hertz(Hz)

Below is a

Thin-lens equation (also works for mirrors)

1/f=1/u+1/v

Where f is the focal length, u is distance of object,v is the distance between the optical centre and the image of the object.

6 0

3 years ago

A hydraulic car jack needs to be designed so it can lift a 2903.57 lb car assuming that a person can exert a force of 24.41 lbs.

marishachu [46]

Answer:

Diameter of the piston would be 0.71 m (71.1 cm)

Explanation:

From the principle of pressure;

$\frac{F_{1} }{A_{1} }$ = $\frac{F_{2} }{A_{2} }$

Let $F_{1}$ = 2903.57 lb, $F_{2}$ = 24.41 lbs, $r_{2}$ = 3.26 cm = 0.0326 m.

$A_{2}$ = $\pi r^{2}$

= $\frac{22}{7}$ x $(0.0326)^{2}$

= 0.00334 $m^{2}$

So that:

$\frac{2903.57}{A_{1} }$ = $\frac{24.41}{0.00334}$

$A_{1}$ = $\frac{2903.57*0.00334}{24.41}$

= 0.3973

$A_{1}$ = 0.4 $m^{2}$

The radius of the piston can be determined by:

$A_{1}$ = $\pi r^{2}$

0.3973 = $\frac{22}{7}$ x $r^{2}$

$r^{2}$ = $\frac{0.3973*7}{22}$

= 0.1264

r = $\sqrt{0.1264}$

= 0.3555

r = 0.36 m

Diameter of the piston = 2 x r

= 2 x 0.3555

= 0.711

Diameter of the piston would be 0.71 m (71.1 cm).

4 0

3 years ago

Find the value of x in this figure

liraira [26]

Answer:

x=50

Explanation:

6 0

3 years ago

Read 2 more answers

How many neutrons are there in the neutral atom of 20 10Ne? 1. 22 2. 20 3. 12 4. 9 5. 10

vaieri [72.5K]

Answer:

3.) 12

Explanation:

an atomic number is 11 which means this atom will have 11 protons. the atomic mass is 23 which also means 23-11 is 12 neurons.

4 0

3 years ago

A ball of mass m is thrown into the air in a 45° direction of the horizon, after 3 seconds the ball is seen in a direction 30° f

Rzqust [24]

Answer:

Velocity (magnitude) is 98.37 m/s

Explanation:

We use the vertical component of the initial velocity, which is:

$v_{0y}=v_0*sin(45)=\frac{\sqrt{2} }{2}v_0$

Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):

$v_{y}=v_{0y}+a*t=\frac{\sqrt{2} }{2}v_0-9.8t$

Now we need to find $v_y$ as a function of $v_0$ . We use the horizontal velocity, which is always the same as follow:

$v_x=v_0cos(45\º)=\frac{\sqrt{2} }{2}v_0=v_{t=3}*cos(30\º) \\$

We know the angle at 3 seconds:

$v_y(t=3)=v_{t=3}*sin(30\º)\\v_{t=3}=\frac{v_y}{sin(30\º)}$

Substitute $v_{t=3}$ in $v_x$ and then solve for $v_y$

$\frac{\sqrt{2} }{2}v_0=\frac{v_y*cos(30\º) }{sin(30\º)} \\v_y=\frac{\sqrt{6} }{6}v_0$

With this expression we go back to the kinematic equation and solve it for initial speed

$\frac{\sqrt{6} }{6} v_0 =\frac{\sqrt{2} }{2}v_0-29.4\\v_0(\frac{\sqrt{6}-3\sqrt{2}}{6} )=-29.4\\v_0=98.37 m/s$

3 0

4 years ago