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2 years ago

Three objects have velocities that vary with time

Physics

2 answers:

olganol [36]2 years ago

8 0

Answer:

See below ~

Explanation:

Question 21 :

⇒ v = u + at

⇒ v = 5 + 1.3 (2)

⇒ v = 5 + 2.6

⇒ v = 7.6 m/s

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Question 22 : At t = 3

<u>Subpart (a)</u>

⇒ Object 1 : v = 2 + 3(3) = 11 m/s

⇒ Object 2 : v = -8 - 4(3) = -20 m/s

⇒ Object 3 : v = 1 - 5(3) = -14 m/s

⇒ Hence, their velocities are in the order : Object 2 < Object 3 < Object 1

<u>Subpart (b)</u>

⇒ Object 1 : v = | 2 + 3(3) | = 11 m/s

⇒ Object 2 : v = | -8 - 4(3) | = 20 m/s

⇒ Object 3 : v = | 1 - 5(3) | = 14 m/s

⇒ Hence, their speeds are in the order : Object 1 < Object 3 < Object 2

Solnce55 [7]2 years ago

7 0

#21

initial velocity=u=5m/s
Time=t=2s
Acceleration=a=1.3m/s²

According to first equation of kinematics

v=u+at
v=5+1.3(2)
v=5+2.6
v=7.6m/s

#22

v1=2+3(3)=2+9=11m/s
v2=-8-4(3)=-20m/s
v3=1-5(3)=-14m/s

The order is

v2<V3<v1

for speed find absolute velocity

S1=|11|=11m/s
S2=|-20|=20m/s
S3=|-14|=14m/s

So order is

S1<S3<S2

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3 years ago

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In the given question, the direction of flow of current through the wires is opposite, thus both wires applies the same field on each other. The result to repulsion between them.

The magnetic field (B) between the given wires can be determined by:

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where: I is the current, r is the distance between the wires and $U_{0}$ is the magnetic field constant.

But, I = 11 A, r = 0.12 m and $U_{0}$ = 4 $\pi$ x $10^{-7}$ Tm/A

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3 years ago

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Answer:

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Explanation:

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m stands for mass

g stands for gravitational constant

h stands for height

v stands for velocity

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Part B

The potato is in uniform circular motion so the acceleration is given by

a = v² / r

a stands for centripetal acceleration

According to Newton second law the acceleration is directly proportional to applied force and inversely proportional to the mass of object

So ∑ F = m × a

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Tension force - Force due to weight = m×a

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T = m ×(v²/l) + m×g

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T = .3 ( 45.08/2.30) + 2.94

T = .3 (19.6) +2.94

T = 5.88 + 2.94

T = 8.82 N

The tension in the string is 8.82 N

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