Answer:

Explanation:
We should first find the velocity and acceleration functions. The velocity function is the derivative of the position function with respect to time, and the acceleration function is the derivative of the velocity function with respect to time. 

Similarly, 

Now, the angle between velocity and acceleration vectors can be found. 
The angle between any two vectors can be found by scalar product of them: 

So, 

At time t = 0, this equation becomes

 
        
             
        
        
        
Answer: 88.2 J
Explanation: PE, OR Potential Energy, equals to mass gravity and height.
mass - 3kg
height - 3 because (8-5)
gravity is 9.8kg
so 3 times 3 times 9.8 = 88.2J
 
        
             
        
        
        
Answer:
f.The period is independent of the suspended mass.
Explanation:
The period of a pendulum is given by

where
L is the length of the pendulum
g is the acceleration due to gravity
From the formula, we see that:
1) the period of the pendulum depends only on its length, L, and it is proportional to the square root of the length
2) the period does not depend neither on the mass of the pendulum, nor on its amplitude of oscillation
So, the only correct statements are
f.The period is independent of the suspended mass.
Note: statement "e.The period is proportional to the length of the wire" is also wrong, because the period is NOT proportional to the length of the wire, but it is proportional to the square root of it.
 
        
             
        
        
        
Answer:
8977.7 kg/m^3
Explanation:
Volume of water displaced = 55 cm^3 = 55 x 10^-6 m^3
Reading of balance when block is immersed in water = 4.3 N 
According to the Archimedes principle, when a body is immersed n a liquid partly or wholly, then there is a loss in the weight of body which is called upthrust or buoyant force. this buoyant force is equal to the weight of liquid displaced by the body. 
Buoyant force = weight of the water displaced by the block 
Buoyant force = Volume of water displaced x density of water x g 
                         = 55 x 10^-6 x 1000 x .8 = 0.539 N
True weight of the body = Weight of body in water + buoyant force 
m g = 4.3 + 0.539 = 4.839
m = 0.4937 kg 
Density of block = mass of block / volume of block 
= 
Density of block = 8977.7 kg/m^3
 
        
             
        
        
        
Answer:
It would mean less transpiration and the groundwater would start to make a landslide with no tree root to hold the earth in place