Answer: mg/Cosθ
Explanation:
Taking horizontal acceleration of wedge as 'a' 
FCosΘ = FsinΘ
F = mass(m) × acceleration(a) = ma
For horizontal resolution g = 0
Therefore, 
Horizontal = Vertical 
maCosΘ = mgSinΘ
aCosΘ = gSinΘ
a = gSinΘ/CosΘ
Recall from trigonometry :
SinΘ/Cosθ = tanΘ
Therefore, 
a = gtanΘ
Normal force acing on the wedge:
mgCosΘ + maSinΘ - - - - (y) 
Substitute a = gtanΘ into (y) 
mgCosΘ + mgtanΘsinΘ
tanΘ = sinΘ/cosΘ
mgCosΘ + mgsinΘ/cosΘsinΘ
mgCosΘ + mgsin^2Θ/cosΘ
Factorizing
mg(Cosθ + sin^2Θ/cosΘ)
Taking the L. C. M
mg[(Cos^2θ + sin^2Θ) /Cosθ] 
Recall: Cos^2θ + sin^2Θ = 1
mg[ 1 /Cosθ] 
mg/Cosθ
 
        
             
        
        
        
Answer: 37.981 m/s
Explanation:
This situation is related to projectile motion or parabolic motion, in which the travel of the ball has two components: <u>x-component</u> and <u>y-component.</u> Being their main equations as follows:
<u>x-component:
</u>
 (1)
   (1)
Where:
 is the point where the ball strikes ground horizontally
 is the point where the ball strikes ground horizontally
 is the ball's initial speed
 is the ball's initial speed
 because we are told the ball is thrown horizontally
 because we are told the ball is thrown horizontally
 is the time since the ball is thrown until it hits the ground
 is the time since the ball is thrown until it hits the ground
<u>y-component:
</u>
 (2)
   (2)
Where:
 is the initial height of the ball
  is the initial height of the ball
 is the final height of the ball (when it finally hits the ground)
  is the final height of the ball (when it finally hits the ground)
 is the acceleration due gravity
  is the acceleration due gravity
Knowing this, let's start by finding  from (2):
 from (2):
<u></u>
 (3)
   (3)
 
   
 (4)
   (4)
 (5)
   (5)
 (6)
   (6)
Then, we have to substitute (6) in (1):
 (7)
   (7)
And find  :
:
 (8)
   (8)
 (9)
   (9)
 (10)
   (10)
On the other hand, since we are dealing with constant acceleration (due gravity) we can use the following equation to find the value of the ball's final velocity  :
:
 (11)
 (11)
 (12)
 (12)
 (13) This is the ball's final velocity, and the negative sign indicates its direction is downwards.
 (13) This is the ball's final velocity, and the negative sign indicates its direction is downwards.
However, we were asked to find the <u>ball's final speed</u>, which is the module of the ball's final vleocity vector. This module is always positive, hence the speed of the ball just before it strikes the ground is 37.981 m/s (positive).
 
        
             
        
        
        
Answer: A and B 
Explanation:
A
The wavelength of both transverse and longitudinal waves is measured parallel to the direction of the travel of the wave.
Because wavelength is the distance between the two successful crest or trough.
B) 
Amplitude of longitudinal waves is measured at right angles to the direction of the travel of the wave and represents the maximum distance the molecule has moved from its normal position.
Because amplitude is the measure of maximum displacement from the original position