Answer:
The nail exerts a force of 573.88 Pounds on the Hammer in positive j direction.
Explanation:
Since we know that the force is the rate at which the momentum of an object changes.
Mathematically 
The momentum of any body is defines as 
In the above problem we see that the moumentum of the hammer is reduced to zero in 0.023 seconds thus the force on the hammer is calculated using the above relations as


When a psychologist simply records the relationship between two variables without manipulating them, it is called a correlational study.
The observed relationship does not by itself reveal which variable causes the other. This is the directionally problem. Also, the relationship may be due to a third variable controlling both of the observed variables.
Answer:
a) 
b) 
c) 
d) 
Explanation:
Non horizontal pipe diameter, d = 25 cm = 0.25 m
Radius, r = 0.25/2 = 0.125 m
Entry temperature, T₁ = 304 + 273 = 577 K
Exit temperature, T₂ = 284 + 273 = 557 K
Ambient temperature, 
Pipe length, L = 10 m
Area, A = 2πrL
A = 2π * 0.125 * 10
A = 7.855 m²
Mass flow rate,

Rate of heat transfer,

a) To calculate the convection coefficient relationship for heat transfer by convection:

Note that we cannot calculate the heat loss by the pipe to the environment without first calculating the surface temperature of the pipe.
c) The surface temperature of the pipe:
Smear coefficient of the pipe, 

b) Heat loss from the pipe to the environment:

d) The required fan control power is 25.125 W as calculated earlier above
Answer:
A combination square is a multi-use measuring instrument which is primarily used for ensuring the integrity of a 90° angle, measuring a 45° angle, measuring the center of a circular object, find depth, and simple distance measurements. It can also be used to determine level and plumb using its spirit level vial.
Explanation: