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2 years ago

What is a convex lens?

2 answers:

6 0

The convex lens is a lens that converges rays of light that convey parallel to its principal axis (i.e. converges the incident rays towards the principal axis) which is relatively thick across the middle and thin at the lower and upper edges. The edges are curved outward rather than inward.

Lana71 [14]2 years ago

6 0

A lens bound by two spherical surfaces bulging outwards and a single piece of glass that curves outward and converges the light incident on it are both convex lenses

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How much larger is the diameter of Jupiter compared to the diameter of Saturn?

allsm [11]

Really long we’ll not long but far in distance

5 0

2 years ago

The Cosmo Clock 21 Ferris wheel in Yokohama, Japan, has a diameter of 100 m. Its name comes from its 60 arms, each of which can

Sonja [21]

Answer:

Explanation:

a ) speed of passenger = circumference / time

= 2π R / Time

= 2 x 3.14 x 50 / 60

= 5.23 m /s

b )

centrifugal force = m v² /R

= (882 /9.8 ) x 5.23² / 50

= 77.47 N

Apparent weight at the highest point

real weight - centrifugal force

= 882 - 77.47

= 804.53 N

Apparent weight at the lowest point

real weight + centrifugal force

= 882 +77.47

= 959.47 N

c ) if the passenger’s apparent weight at the highest point were zero

centrifugal force = weight

mv² /R = mg

v² = gR

= 9.8 X 50

v = 22.13 m /s

d )

apparent weight

mg - mv² / R

= 882 - (882 / 9.8 )x 22.13²/50

= 882 + 882

= 1764 N

6 0

3 years ago

A car, X, with a mass of 1500 kg is moving west with an acceleration of 0.50 m/s2. A second car, Y, of equal mass is heading eas

ehidna [41]

Answer:

Explanation:

8 0

3 years ago

Please help!!! A river has a constant current of 3 km per hour. If a motorboat, capable of maintaining a constant speed of 20km

PilotLPTM [1.2K]

Construct a vector diagram. It will be a right-angled triangle. One vector (the hypotenuse) represents the heading of the boat, one represents the current and one represents the resultant speed of the boat, which I'll call x. Their magnitudes are 20, 3 and x. Let the required angle = theta. We have:

theta = arcsin(3/20) = approx. 8.63° 

The boat should head against the current in a direction approx. 8.63° to the line connecting the dock with the point opposite, or approx. 81.37° to the shore line. 

x = sqrt(20^2 - 3^2) 
= sqrt(400 - 9) 
= sqrt 391 

The boat's crossing time = 
0.5 km/(sqrt 391 km/hr) 
= (0.5/sqrt 391) hr 
= approx. 0.025 hr 
= approx. 91 seconds

4 0

3 years ago

A box is placed on a conveyor belt that moves with a constant speed of 1.05 m/s. The coefficient of kinetic friction between the

sveticcg [70]

Answer:

The box stops in 0.139 seconds, after moving 7.29cm (0.0729m) backwards relative to the belt.

Explanation:

As the box is initially at rest relative to the earth, it is moving backwards with a speed of 1.05m/s relative to the belt. Then, the frictional force acts on the box to make it stop relative to the belt. So, we first have to write the equations of motion of the box in each axis:

$x: f_k=ma\implies a=\frac{f_k}{m} \\\\y: N-mg=0\implies N=mg$

Since the frictional force $f_k$ is equal to $f_k=\mu_k N=\mu_k mg$ , then we have that the acceleration is:

$a=\frac{\mu_k mg}{m}=\mu_k g$

Now, from the definition of acceleration we get:

$a=\frac{v-v_0}{t}\implies t=\frac{v-v_0}{a}$

And, as the final velocity is zero because the box gets to a stop, we have:

$t=-\frac{v_0}{a}=-\frac{v_0}{\mu_k g}$

(Don't worry about the negative sign. It will disappear because the initial velocity is also negative, since we take the box initially moving backwards)

Then, plugging in the given values, we calculate the time:

$t=-\frac{(-1.05m/s)}{0.770(9.81m/s^{2})}=0.139s$