Answer: a) 7.1 * 10^3 N; b) -880 N directed out of the curve.
Explanation: In order to solve this problem we have to use the Newton laws, then we have the following:
Pcos 15°-N=0
Psin15°-f= m*ac
from the first we obtain N, the normal force
N=750Kg*9.8* cos (15°)= 7.1 *10^3 N
Then to calculate the frictional force (f) we can use the second equation
f=P sin (15°) -m*ac where ac is the centripetal acceletarion which is equal to v^2/r
f= 750 *9.8 sin(15°)-750*(85*1000/3600)^2/150= -880 N
Answer:
Please find the answer in the explanation
Explanation:
Friction is a force that opposes motion. One or two of the advantages of friction are break and ability of an object to walk.
Writing yes it is useful because when your writing because friction helps you see what your writing
ii. Rubbing. Yes, it is useful.
friction make it possible for two object to rub each other
iii. Skiing. No. It is not useful because With presence of friction, skiing will not be possible.
iv. Rotating a wheel No. It is not useful because Friction will oppose the rotation of the wheel.
Tobacco smoking is an unhealthy habit which can cause cancer due to the presence of more than 5000 chemicals, some of which are carcinogens (a chemical that causes cancer). It is the smoke itself, that carries carcinogens to the lungs and can eventually lead to the development of diseases such as lung cancer.
The period of a wave is the time it takes the wave to complete one cycle (at a fixed location).
So if a wave completes one cycle in <em>2 seconds</em>, then that is its period.
Answer:
The gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
the acceleration a = 7.8 m/s²
Explanation:
Given that :
the mass of the skydiver = 60 kg
Velocity = 50 m/s
Thus; gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
Also; the air resistance is acting upward and the resultant of both forces = mass×acceleration
So;
mg-R = ma
60(9.8) - 120 = 60(a)
588 -120 = 60a
468 = 60a
a = 
a = 7.8 m/s²
Hence, the acceleration a = 7.8 m/s²
