Answer: 
Explanation:
Given
Length of plank is 1.6 m
Force
is applied on the left side of plank
Force
is applied 43 cm from the left end O.
Mass of the plank is 
for equilibrium
Net torque must be zero. Taking torque about left side of the plank

Net vertical force must be zero on the plank

Answer:

Explanation:
We can use the conservation of momentum. The initial momentum is equal to the final momentum:
x-coordinate

(1)
y-coordinate

(2)
We can divide equations (2) and (1):



I hope it helps you!
<h3>2
Answers:</h3>
a) Velocity is a vector quantity
e) Velocity is a speed with direction
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Explanation:
If we know the velocity of an object, then we know how fast it's going (speed) and where it's going (direction). It is a vector because the direction of the vector determines the direction, and the length of the vector (aka magnitude) determines the speed. So in a sense we've built in two facts of data into one visual.
An example of velocity: 10 miles per hour north. Here we have the speed of 10 mph and the direction north.
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Extra info:
- Choice B contradicts choice A, so we can cross choice B off the list.
- Choice C is false because speed is a scalar, or single quantity, and not a vector. As mentioned earlier, speed is a part of velocity, but they aren't the same exact thing.
- Choice D is false because the velocity does not account for net force. We don't have any force information built into the velocity.
Answer:
Yoga is really good. it helps expand your mind, as well as to stay in shape.
Answer:
Factors determining the state of substances
* Inter molecular force : substances having strong intermolecular force will be solid and substance with weak inter molecular force will be gas.
* Nature of chemical bond:
Ionic compounds are generally solid in nature because of strong intermolecular force.
Polar covalent compounds may be solid or liquid
Non polar covalent compounds generally gas
* Electro negativity difference: greater the electronegativity difference, greater will be the intermolecular force.