Answer:
She is measuring her speed
Explanation:
Speed is defined as the ratio between the distance covered divided by the time taken to cover that distance:
where
d is the distance covered
t is the time taken
Since Mary is measuring how far she can run in a given period of time, she is measuring the distance she can travel (d) in a given time (t), so she is measuring her speed.
Part a
Just use v=d/t
d = vt
d = 7 x 1.5
For part b
Vf=Vi +at
Vf=0 + (9.8)(1.5)
d= ((Vi + Vf) /2) x t
d = ((0 + Vf) /2) x 1.5
In second equation, use Vf found in first equation
Complete question is;
a. Two equal sized and shaped spheres are dropped from a tall building. Sphere 1 is hollow and has a mass of 1.0 kg. Sphere 2 is filled with lead and has a mass of 9.0 kg. If the terminal speed of Sphere 1 is 6.0 m/s, the terminal speed of Sphere 2 will be?
b. The cross sectional area of Sphere 2 is increased to 3 times the cross sectional area of Sphere 1. The masses remain 1.0 kg and 9.0 kg, The terminal speed (in m/s) of Sphere 2 will now be
Answer:
A) V_t = 18 m/s
B) V_t = 10.39 m/s
Explanation:
Formula for terminal speed is given by;
V_t = √(2mg/(DρA))
Where;
m is mass
g is acceleration due to gravity
D is drag coefficient
ρ is density
A is Area of object
A) Now, for sphere 1,we have;
m = 1 kg
V_t = 6 m/s
g = 9.81 m/s²
Now, making D the subject, we have;
D = 2mg/((V_t)²ρA))
D = (2 × 1 × 9.81)/(6² × ρA)
D = 0.545/(ρA)
For sphere 2, we have mass = 9 kg
Thus;
V_t = √[2 × 9 × 9.81/(0.545/(ρA) × ρA))]
V_t = 18 m/s
B) We are told that The cross sectional area of Sphere 2 is increased to 3 times the cross sectional area of Sphere 1.
Thus;
Area of sphere 2 = 3A
Thus;
V_t = √[2 × 9 × 9.81/(0.545/(ρA) × ρ × 3A))]
V_t = 10.39 m/s
They will feel equally hot or cold at the same temperature.
What do you mean by temperature?
Temperature is a physical parameter that describes how hot stuff or radiation is. There are 3 different types of temperature scales: those described in regards to the average translational kinetic energy per freely moving microscopic substance in a body, such as a atom, compound, or anion, such as the SI scale; those that rely solely on purely <u>macroscopic properties and thermodynamic principles</u>, such as Kelvin's original definition; <u>and those that are not defined by theoretical principles, but are defined by convenient empirical properties of particulate matter.</u>
If they are the same temperature as the area of your body that is touching them, they will feel equally hot or cold. There will be no heat movement if the wood and iron at the same temperature as the skin, and the iron's higher thermal conductivity will be irrelevant. <u>The </u><u>specific temperature</u><u> cannot be specified because if you touch the materials with your fingertips, the wood and iron must match that</u><u> temperature</u><u>, and if you test them with your tongue, which is often considerably </u><u>warmer </u><u>than your hands, the wood and iron must be </u><u>warmer</u><u>.</u>
To know more about temperature, click on the link
brainly.com/question/13165448
#SPJ10