A wave that transfers energy through vibrating In a medium
Answer:
the minimum time interval is 0.77 seconds
Explanation:
given data
coefficient of static friction = 0.5
coefficient of static friction shoes= 0.825
travel s = 2.40 m
to find out
what is the minimum time interval
solution
we know newton 2nd law
force = mass × acceleration
and
force acting on person due to friction
force = coefficient of static friction shoes × mg
so we can say
coefficient of static friction shoes × mg = ma
so
a = coefficient of static friction shoes × g
and we know g is 9.8 m/s²
so
distance formula by kinematic relation
distance = ut + 0.5 × at²
here put a value and u is zero because initial speed
2.40 = 0 + 0.5 × coefficient of static friction shoes × g× t²
2.40 = 0.5 × 0.825 × 9.8 × t²
t = 0.77 s
the minimum time interval is 0.77 seconds
<u>Answer:</u>
For 1: The correct option is Option C.
For 3: The final velocity of the opponent is 1m/s
<u>Explanation: </u>
During collision, the energy and momentum remains conserved. The equation for the conservation of momentum follows:
...(1)
where,
are the mass, initial velocity and final velocity of first object
are the mass, initial velocity and final velocity of second object
<u>For 1:</u>
We are Given:

Putting values in equation 1, we get:

Hence, the correct answer is Option C.
Impulse is defined as the product of force applied on an object and time taken by the object.
Mathematically,

where,
F = force applied on the object
t = time taken
J = impulse on that object
Impulse depends only on the force and time taken by the object and not dependent on the surface which is stopping the object.
Hence, the impulse remains the same.
Let the speed in right direction be positive and left direction be negative.
We are Given:

Putting values in equation 1, we get:

Hence, the final velocity of the opponent is 1m/s and has moved backwards to its direction of the initial velocity.
Answer:
Revolutions made before attaining angular velocity of 30 rad/s:
θ = 3.92 revolutions
Explanation:
Given that:
L(final) = 10.7 kgm²/s
L(initial) = 0
time = 8s
<h3>
Find Torque:</h3>
Torque is the rate of change of angular momentum:

<h3>Find Angular Acceleration:</h3>
We know that
T = Iα
α = T/I
where I = moment of inertia = 2.2kgm²
α = 1.34/2.2
α = 0.61 rad/s²
<h3>
Find Time 't'</h3>
We know that angular equation of motion is:
ω²(final) = ω²(initial) +2αθ
(30 rad/s)² = 0 + 2(0.61 rad/s²)θ
θ = (30 rad/s)²/ 2(0.61 rad/s²)
θ = 24.6 radians
Convert it into revolutions:
θ = 24.6/ 2π
θ = 3.92 revolutions
<h3><u>Answer;</u></h3>
B. constant acceleration.
<h3><u>Explanation</u>;</h3>
- Free fall is the type of motion of a body or an object when only gravity is acting on it.
- <em><u>All objects undergo free fall on the earth surface at the same rate irrespective of their mass. This is because the gravitational field on the surface of the earth 9.8 N/kg, causes and acceleration equivalent to 9.8 m/s/s of any object in free fall motion.</u></em>
- Therefore,<u> the acceleration of any freely falling object near the surface of the earth is 9.8 m/s².</u>