Answer:
T = 15 kN
F = 23.33 kN
Explanation:
Given the data in the question,
We apply the impulse momentum principle on the total system,
mv₁ + ∑
= mv₂
we substitute
[50 + 3(30)]×10³ × 0 + FΔt = [50 + 3(30)]×10³ × ( 45 × 1000 / 3600 )
F( 75 - 0 ) = 1.75 × 10⁶
The resultant frictional tractive force F is will then be;
F = 1.75 × 10⁶ / 75
F = 23333.33 N
F = 23.33 kN
Applying the impulse momentum principle on the three cars;
mv₁ + ∑ = mv₂
[3(30)]×10³ × 0 + FΔt = [3(30)]×10³ × ( 45 × 1000 / 3600 )
F(75-0) = 1.125 × 10⁶
The force T developed is then;
T = 1.125 × 10⁶ / 75
T = 15000 N
T = 15 kN
Answer:
D. Brake
Explanation:
NJMVC is an acronym for New Jersey Motor Vehicle Commission and it is an agency of government that was established in 2003. NJMVC is saddled with the responsibility of inspecting, titling of number plates and registration of motor vehicles, as well as licensing of drivers in New Jersey, United States of America.
The NJMVC subject the applicants (drivers) to a series of test before they are issued a valid driver's license, some of these tests include;
1. Vision test.
2. Knowledge test.
3. Road test.
All of the above mentioned tests must be passed by a driver before he or she are issued a valid driver's license.
Some of the test drive requirements are;
- Valid registration documents.
- Valid sticker of inspection.
- No obstacle or center consoles should prevent the examiner from accessing both the foot brake and parking brake.
Hence, NJMVC will reject a vehicle from the road test if the examiner does not have access to a brake. Thus, the brakes are required to be in good working condition prior to the road test.
However, if an applicant (driver) passes the road test he or she would be issued an authorization for licensing by the examiner and then a digital driver's license by the motor vehicle commission.
Answer:
Height of tower equals 122.5 meters.
Explanation:
Since the height of the tower is 'H' the total time of fall of stone 't' is calculated using second equation of kinematics as
Since the distance covered in last 1 second is 
and the total distance covered in 't' seconds is 'H' thus the distance covered in the first (t-1) seconds of the motion equals
Now by second equation of kinematics we have
Thus we have
Dividing i by ii we get
Thus from equation ii we obtain 'H' as
