Answer: a. a leaping frog
Explanation: In a projectile motion the object must have a certain path or trajectory with respect to a certain angle. For the leaping frog its velocity can be resolve into components having the final velocity at the highest point to be zero.
Answer:<span>Humid air is lighter, so it has lower pressure.
The reason is the molecules of water are H2O, whose molar mass is 18 g/mol.
These molecules displaces molecules of N2 and O2, whose molar masses are:
N2: 2*14g/mol = 28 g/mol, and
O2: 2*16g/mol = 32 g/mol.
Then molecules of 28g/mol and 32 g/mol are being replaced with molecules of 18g/mol, leading to a lower weight of the same volume of air, which results in lower pressure.
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Answer:
v (minimum speed) = 2.90 m/sec.

Maximum value of speed will occur at lowest point of vertical circle.
Explanation:
a) What minimum speed is necessary so that there is no tension in the string at the top of the circle but the rock stays in the same circular path?
Using the force balance expression at the top of the circle,
Gravitational Force + Tension force = Centrifugal force

Given that : T = 0
R = length of string = 0.86 m
mass of the spinning rock = 0.75 kg


v (minimum speed) = 2.90 m/sec.
b) what is the maximum speed the rock can have so that the string does not break?
Here the force balance at bottom of circle is represented by the illustration:

Given that:
maximum tension T = 45 N
maximum speed v = ??
mass m = 0.75 kg
∴

c)
At what point in the vertical circle does this maximum value occur?
Maximum value of speed will occur at lowest point of vertical circle.
This is so because at the lowest point; the tension in string will be maximum.
Answer:
brooo it is rotation .............