Answer:
Impulse = 90
Resulting Velocity = 89
Explanation:
Use F * change in time = m * change in velocity.
For the first part of the question, the left side of the equation is the impulse. Plug it in.
60 * (3.0 - 0) = 90.
For the second half. we use all parts of the equation. I'm gonna use vf for the final velocity.
60 * (3.0 - 0) = 10 * (vf - 80). Simplify.
90 = 10vf - 800. Simplify again.
890 = 10vf. Divide to simplify and get the answer.
The resulting velocity is 89.
<h2>Solution :</h2>
Here ,
• Height of sign post = 30 m
• Distance between signpost and truck = 24 m
Let the
• Top of signpost = A
• Bottom of signpost = B
• The end of truck facing sign post be = C
Now as we can clearly imagine that the ladder will act as an hypotenuse to the Triangle ABC .
Where
• AB = Height of signpost = 30 m
• BC = distance between both = 24 m
• AC = Minimum length of ladder
→ AC² = AB² + BC² ( As we can see AB is perpendicular to BC )
→ AC² = (30)² + (24)²
→ AC² = 900 + 576
→ AC² = 1476
→ AC = 38.41875
or AC apx = 38.42
So minimum height of ladder = 38.42
Answer:34 cm
Explanation:
Given
mass of meter stick m=80 gm
stick is balanced when support is placed at 51 cm mark
Let us take 5 gm tack is placed at x cm on meter stick so that balancing occurs at x=50 cm mark
balancing torque






As the question is about changing in frequency of a wave for an observer who is moving relative to the wave source, the concept that should come to our minds is "
Doppler's effect."
Now the general formula of the Doppler's effect is:

-- (A)
Note: We do not need to worry about the signs, as everything is moving towards each other. If something/somebody were moving away, we would have the negative sign. However, in this problem it is not the issue.
Where,
g = Speed of sound = 340m/s.

= Velocity of the receiver/observer relative to the medium = ?.

= Velocity of the source with respect to medium = 0 m/s.

= Frequency emitted from source = 400 Hz.

= Observed frequency = 408Hz.
Plug-in the above values in the equation (A), you would get:


Solving above would give you,

= 6.8 m/s
The correct answer = 6.8m/s
Answer:
upwards
Explanation:
Torque is the vector cross product of the force and radial distance.


The direction of the torque would be perpendicular to the direction of the force and radial distance. The direction of the force is counter-clockwise. The direction of the torque would be upwards.