Answer: - 7500N
Explanation:
Given the following :
Initial Velocity of car = 108km/hr
Time taken to stop after applying brakes = 4s
Mass of passengers in car = 1000kg
Force exerted by the brakes on the car =?
After 4s, then final Velocity (V) = 0
Initial Velocity (u) of the car = 108km/hr
108km/hr = (108 × 1000)m ÷ (3600)s = 30m/s
Force exerted = mass(m) × acceleration(a)
Acceleration of car = Change in Velocity with time
a = (v - u) / t
a = (0 - 30) / 4
a = - 30/ 4
a = - 7.5m/s^2
Therefore,
Force exerted = mass(m) × acceleration(a)
Force exerted = 1000kg × (-7.5)m/s^2
Force exerted = - 7500N
Answer:
: Rocket weight on earth
: Rocket weight on moon
Explanation:
Conceptual analysis
Weight is the force with which a body is attracted due to the action of gravity and is calculated using the following formula:
W = m × g Formula (1)
W: weight
m: mass
g: acceleration due to gravity
The mass of a body on the moon is equal to the mass of a body on the earth
The acceleration due to gravity on a body is different on the moon and on the earth
Equivalences
1 slug = 14.59 kg
Known data



Problem development
To calculate the weight of the rocket on the moon and on earth we replace the data in formula (1):
: Rocket weight on earth
: Rocket weight on moon
Answer:

Explanation:
Given data:
Thickness of aluminium sheet 10 cm
initial temperature = 25 degree celcius
Assumption
Thermal properties remain constant, transfer of heat by radiation is negligible.
from the information given in the question we have
T_S ≈T_∞ , it implies we have h → ∞
from table 4.2 Biot number → ∞ the value of

The fourier number is

Temperature at center after 15 second of heating




Explanation:
I don't have time for you
I think the answer for the question above its b 1.2