Through emotion, facial expressions, body language, etc...
hope this helps
Answer:
Vf = 3.67 [m/s]
Explanation:
To solve this problem we must use the following equation of kinematics.

where:
Vf = final velocity [m/s]
Vi = initial velocity = 4.3 [m/s]
a = acceleration or desacceleration = 0.5 [m/s²]
x = distance = 5 [m]
Note: The negative sign in the above equation means that the velocity of the ball is decreasing (desacceleration).
Now replacing:
Vf² = (4.3)² - (2*0.5*5)
Vf² = 18.49 - 5
Vf² = 13.49
using the square root, we have.
Vf = 3.67 [m/s]
Answer:
So percentage error will be 2 %
Explanation:
We have given initial value of acceleration due to gravity 
And final value of acceleration due to gravity 
We have to find the percentage error
We know that percentage error is given by 
So
%
Answer:
68cm
Explanation:
You can solve this problem by using the momentum conservation and energy conservation. By using the conservation of the momentum you get

m: mass of the bullet
M: mass of the pendulum
v1: velocity of the bullet = 410m/s
v2: velocity of the pendulum =0m/s
v: velocity of both bullet ad pendulum joint
By replacing you can find v:

this value of v is used as the velocity of the total kinetic energy of the block of pendulum and bullet. This energy equals the potential energy for the maximum height reached by the block:

g: 9.8/s^2
h: height
By doing h the subject of the equation and replacing you obtain:

hence, the heigth is 68cm
Answer:
Explanation:
First of all, I used the specific heat of water as 4182 J/(kgC) and the specific heat of ethyl alcohol (EtOH) as 2440 J/(kgC); that means that we need the masses in kg, not g.
120.g = .1200 kg of ethyl alcohol. Now for the formula:
where spheat is specific heat.
Filling that horrifying-looking formula in with some values:
and
and
16(4182x + 292.8) = 83640x + 2928 and
66912x + 4684.8 = 83640x + 2928 and
1756.8 = 16728x so
x = .105 kg and the amount of water added is 105 g