First, we have to calculate the normal forces on different surfaces.The normal force on the 4.00 kg, N1 = (4)(9.8) = 39.2 N. The normal force on the 10.0 kg, N2 = (14)(9.8) = 137.2 N. Looking at the 10.0 kg block, the static forces that counteract the pulling force equals the sum of the friction from the two surfaces. Fc = N1 * 0.80 + N2 * 0.80 = 141.12 N. Since the counter force is less than the pulling force, the blocks start to move and hence, kinetic frictions are considered.
Therefore, f1 = uk * N1 = (0.60)(39.2) = 23.52 N.
Look on this website http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/sinslit.html
Answer:
So length of pendulum is 143.129 m
Explanation:
We have given period of simple pendulum is 2 sec
We have to find the length of simple pendulum
Let the length of pendulum is l
Acceleration due to gravity
is
Time period is given by 
So 

Squaring both side

l =143.129 m
So length of pendulum is 143.129 m
Answer:
The value of total energy needed per minute for the humidifier = 77.78 KJ
Explanation:
Total energy per minute the humidifier required = Energy required to heat water to boiling point) + Energy required to convert liquid water into vapor at the boiling point) ----- (1)
Specific heat of water = 4190 
The heat of vaporization is = 2256 
Mass = 0.030 kg
Energy needed to heat water to boiling point = 
Energy needed to heat water to boiling point = 0.030 × 4.19 × (100 - 20)
Energy (
) = 10.08 KJ
Energy needed to convert liquid water into vapor at the boiling point
= 0.030 × 2256 = 67.68 KJ
Thus the total energy needed E =
+ 
E = 10.08 + 67.68
E = 77.78 KJ
This is the value of total energy needed per minute for the humidifier.
Answer:
Fp = 26.59[N]
Explanation:
This problem can be solved using the principle of work and energy conservation, i.e. the final kinetic energy of a body will be equal to the sum of the forces that do work on the body plus the initial kinetic energy.
We need to identify the initial data:
d = distance = 41.9[m]
Ff = friction force = 44.5 [N]
m = mass = 16.3 [kg]
v1 = 1.9 [m/s]
v2 = 12.6 [m/s]
The kinetic energy at the beginning can be calculated as follows:
![E_{k1}= \frac{1}{2}*m*v_{1}^2 \\E_{k1}= \frac{1}{2}*16.3*(1.9)_{1}^2\\E_{k1}= 29.42[J]](https://tex.z-dn.net/?f=E_%7Bk1%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2Am%2Av_%7B1%7D%5E2%20%5C%5CE_%7Bk1%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2A16.3%2A%281.9%29_%7B1%7D%5E2%5C%5CE_%7Bk1%7D%3D%2029.42%5BJ%5D)
And the final kinetic energy.
![E_{k2}= \frac{1}{2}*m*v_{2}^2 \\E_{k2}= \frac{1}{2}*16.3*(12.6)^2\\E_{k2}= 1294[J]](https://tex.z-dn.net/?f=E_%7Bk2%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2Am%2Av_%7B2%7D%5E2%20%5C%5CE_%7Bk2%7D%3D%20%5Cfrac%7B1%7D%7B2%7D%2A16.3%2A%2812.6%29%5E2%5C%5CE_%7Bk2%7D%3D%201294%5BJ%5D)
The work is performed by two forces, the friction force and the pushing force, it is important to clarify that these forces are opposite in direction.
The weight of the cart also performs a work in the direction of movement since the plane is tilted down, this component of the weight of the cart must be parallel to the surface of the inclined plane.
![W_{1-2}=-(44.5*41.9)+(16.3*9.81*sin(17.5)*41.9)+(F_{p}*41.9) \\therefore:\\E_{k1}+W_{1-2}=E_{k2}\\29.42+150.16+(F_{p}*41.9)=1294\\F_{p}=1114.42/41.9\\F_{p}=26.59[N]](https://tex.z-dn.net/?f=W_%7B1-2%7D%3D-%2844.5%2A41.9%29%2B%2816.3%2A9.81%2Asin%2817.5%29%2A41.9%29%2B%28F_%7Bp%7D%2A41.9%29%20%5C%5Ctherefore%3A%5C%5CE_%7Bk1%7D%2BW_%7B1-2%7D%3DE_%7Bk2%7D%5C%5C29.42%2B150.16%2B%28F_%7Bp%7D%2A41.9%29%3D1294%5C%5CF_%7Bp%7D%3D1114.42%2F41.9%5C%5CF_%7Bp%7D%3D26.59%5BN%5D)