Answer:
T = 273 + (-50) = 273 – 50 = 223 K
R = 188.82 J / kg K for CO2
Density (Martian Atmosphere) = P / RT = 900 / 188.92 x 223 = 900 / 42129.16 = 0.0213 kg / 
T = 273 +18 = 291 K, R = 287 J / kg k (for air) P = 101.6 k Pa = 101600 Pa
Density (Earth Atmosphere) = P / RT = 101600 / 287 x 291 = 1.216 kg /
Answer: The same current flows through bth cables
Explanation:
Lets have a look to the next two equations
The Ohm´s V = I*R (1)
where:
V is voltage (potencial dfference) in volts
I is the electric current in ampers
R is the electric resistance
When a voltage is applied as the electrc load is not specified ( we have to assume is the same) the current will be the same
And in the other hand the resistance R =ρL/s
Where ρ is the resistivity of the conductor L the length and s square section of the conductor
If we assume that the smaller diameter cable is able to conduct the current then nothing happens. The point is that the capacity of conduction of current depend on the section of the cable (the area)
Tables exist where to find the capacity of each cable according to its diameter.
Answer:
The coefficient of kinetic friction 
Explanation:
From the question we are told that
The length of the lane is 
The speed of the truck is 
Generally from the work-energy theorem we have that

Here N is the normal force acting on the truck which is mathematically represented as
is the change in kinetic energy which is mathematically represented as
=>
=>

=> 
=> 
Answer:
Perfectly inelastic collision
Explanation:
There are two types of collision.
1. Elastic collision : When the momentum of the system and the kinetic energy of the system is conserved, the collision is said to be elastic. For example, the collision of two atoms or molecules are considered to be elastic collision.
2. Inelastic collision: When the momentum the system is conserved but the kinetic energy is not conserved, the collision is said to be inelastic. For example, collision of a ball with the mud.
For a perfectly elastic collision, the two bodies stick together after collision.
Here, the meteorite collide with the Mars and buried inside it, the collision is said to be perfectly inelastic. here the kinetic energy of a body lost completely during the collision.
First of all, we can find the mass of the person, since we know his weight W:

And so

We know for Newton's second law that the resultant of the forces acting on the person must be equal to the product between the mass and the acceleration a of the person itself:

There are only two forces acting on the person: his weight W (downward) and the vincular reaction Rv of the floor against the body (upward). So we can rewrite the previous equation as

We know the acceleration of the system,

(upward, so with same sign of Rv), so we can solve to find the value of Rv, the normal force exerted by the elevator's floor on the person: