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jekas [21]
3 years ago
15

12. A boy of mass 50 kg running 5m/s jumps on to a 20kg trolley

Physics
1 answer:
atroni [7]3 years ago
7 0

Answer:

4 m/s

Explanation:

Momentum is conserved.

m₁ v₁ + m₂ v₂ = (m₁ + m₂) v

(50)(5) + (20)(1.5) = (50 + 20) v

v = 4

The final velocity is 4 m/s.

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that our behavior still largely coincides with the positions of the sun.

-- The position of the Moon was originally the primary influence in determining
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6 0
2 years ago
The left end of a long glass rod 8.00 cm in diameter, with an index of refraction 1.60, is ground to a concave hemispherical sur
sp2606 [1]

Answer:

a) q = -9.23 cm, b)  h’= 0.577 mm , c) image is right and virtual

Explanation:

This is an optical exercise, where the constructor equation should be used

        1 / f = 1 / p + 1 / q

Where f is the focal length, p the distance to the object and q the distance to the image

A) The cocal distance is framed with the relationship

       1 / f = (n₂-1) (1 /R₁ -1 /R₂)

In this case we have a rod whereby the first surface is flat R1 =∞ and the second surface R2 = -4 cm, the sign is for being concave

       1 / f = (1.60 -1) (1 /∞ - 1 / (-4))

       1 / f = 0.6 / 4 = 0.15

        f = 6.67 cm

We have the distance to the object p = 24.0 cm, let's calculate

       1 / q = 1 / f - 1 / p

       1 / q = 1 / 6.67 - 1/24

       1 / q = 0.15 - 0.04167 = 0.10833

       q = -9.23 cm

distance to the negative image is before the lens

B) the magnification of the lenses is given by

       M = h ’/ h = - q / p

        h’= - q / p h

        h’= - (-9.23) / 24.0 0.150

        h’= 0.05759 cm

        h’= 0.577 mm

C) the object is after the focal length, therefore, the image is right and virtual

6 0
3 years ago
A pendulum
RSB [31]

Explanation:

The time period rotation of the bob is t and the tension in the thread is T. ... A simple pendulum of length. ... Balancing the forces in Horizontal and vertical direction: ... Circular motion 2.

1 answer

8 0
3 years ago
What happens to the object if the line crosses the x-axis from the positive portion of a velocity versus time diagram?
stealth61 [152]

Answer:

A velocity time graph shows the change of velocity of an object with respect ot time. If the slope of the graph is increasing in the postive region, it means that the velocity is changing, if the slope is decreasing, it means the the velocity is decreasing, but the object is moving in the same direction (positve direction).

If this slope intersects the graph at x-axis, it means that the body has 0 velocity and has become still. After that, if the line enters in the negative region, it means that its velocity is started to increases again, but the body is movinging in the opposite direction (negative direction)

7 0
3 years ago
Which of the following rivers flows north in eastern Florida?
Zarrin [17]

St. John’s

_________

o0o0o0o0o0

6 0
2 years ago
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