Complete Question
Suppose a NASCAR race car rounds one end of the Martinsville Speedway. This end of the track is a turn with a radius of approximately 57.0 m . If the track is completely flat and the race car is traveling at a constant 30.5 m/s (about 68 mph ) around the turn.
Required:
a. What is the race car's centripetal (radial) acceleration?
b. What is the force responsible for the centripetal acceleration in this case?
O normal
O gravity
O friction
O weight
Answer:
question a
question b
correct option is option 3
Explanation:
From the question we are told that
The radius is 
The constant speed at which the race car is travelling is 
Generally from the question we are told that the track is completely flat so the only force pulling the car to the middle is the frictional force hence the centripetal force is due to the frictional force
Generally the centripetal acceleration is mathematically represented as
=> 
=>
Answer:
Explained
Explanation:
Resistance R in a current flow through an object is given by
ρ = resistivity of the material
L= length of the object
A= area of cross section
clearly resistance is directly dependent on length of the object.This means greater the length larger will be resistance to current.
thermal resistance R_th is given by
L= length of the object
A= area of cross section
K = Conductivity of the material
thermal resistance is also is directly dependent on length of the object.This means greater the length larger will be resistance to current.
Answer:
b
Explanation:
they both have a neutral charge so they couldn't be positive or negative since that wouldn't come from anywhere
Answer:
120 mA
Explanation:
The relationship between voltage, current and resistance in a circuit is given by Ohm's law
where
I is the current
V is the voltage
R is the resistance
In this problem, we have an initial current of
I = 60 mA
Then the voltage is doubled:
V' = 2 V
while the resistance is kept the same:
R' = R
So the new current is
so, the current has doubled. Since I = 60 mA, the new current is
Popcorn can be popped by either of the three forms of heat transfer:
Conduction in a pan with hot oil on a stove element.
Convection by an air popper and warm air rising over a heating element... no direct contact with heat source.
Radiation is what occurs in a microwave. Invisible radiant heat activates water molecules in the popcorn.
All the above heat the kernel over 100 Celsius. Water vaporizes/boils (latent heat) and erupts through the kernel.
Mmmm popcorn watch out for the lipids (fat in the oil and butter)
