The point obviously is in the 3rs quadrant
So
စ= tan^-1( y/x)-180
စ= -89.7°
As per the question Bob drops the bag full with feathers from the top of the building.
The mass of the bag(m)= 1.0 lb
Let the air resistance is neglected.As the bag is under free fall ,hence the only force that acts on the bag is the force of gravity which is in vertical downward direction.
Here the acceleration produced on bag due to the free fall will be nothing else except the acceleration due to gravity i.e g =9.8 m/s^2
Here we are asked to calculate the distance travelled by the bag at the instant 1.5 s
Hence time t= 1.5 s
From equation of kinematics we know that -
S=ut + 0.5at^2 [ here S is the distance travelled]
For motion under free fall initial velocity (u)=0.
Hence S= 0×1.5+{0.5×(-9.8)×(1.5)^2}
⇒ -S =0-11.025 m
⇒ S= 11.025 m
=11 m
Here the negative sign is taken only due to the vertical downward motion of the body .we may take is positive depending on our frame of reference .
Hence the correct option is B.
Answer:
T = 0.017s
Explanation:
period is the time it takes a particle to make one oscillation
An electric current is periodic in nature
The current reaches 3.8A ten times.
So there must have been 10 cycles (10 periods) in 0.17s. let 'T' be the period:

t is the total time interval
n is the number of oscillations

10T = 0.17
T = 0.17/10 = 0.017s
Answer:
b) lattice energy
Explanation:
A solution is said to have colligative property when the property depends on the solute present in the solution.
Colligative property depend upon on the solute particle or the ion concentration not on the identity of solute.
osmotic pressure, vapor pressure lowering , boiling point elevation and freezing point lowering all depend upon solute concentration so they will not have colligative property so, the answer remains option 'b' which is lattice energy.