Resistance in Physics The total weight of parachute jumper and parachute is 100 kg. After moving and opening the parachute in high altitude, the parachute will descend at a speed of 5 m / s at a constant speed, and the resistance of parachute jumper and parachute will be calculated

Resistance in Physics The total weight of parachute jumper and parachute is 100 kg. After moving and opening the parachute in high altitude, the parachute will descend at a speed of 5 m / s at a constant speed, and the resistance of parachute jumper and parachute will be calculated

Because it is falling at a constant speed, the force is balanced
F resistance = g = 100kg * 9.8n/kg = 980n

Factors affecting fluid resistance

A fluid does not exert friction on a body at rest, but it exerts resistance on a body moving in it
Roughly speaking, when the viscosity of the fluid is large and the moving object is small and slow, the resistance is proportional to V, √ s and viscosity (V, s are the velocity and cross-sectional area respectively)
In the opposite case, the resistance is proportional to V ^ 2 and s, but not to viscosity
Usually falling, driving or flying in the air belongs to the latter situation

Physics problems about resistance
This is a drawing problem = = but No My camera network line is in my parents' unit
The weight of the object placed on the horizontal ground is 100 n. under the action of horizontal pull f to the left, the object moves in a straight line at a constant speed (the pull is 30 n). Find the horizontal resistance f on it
Just the answer
Of course, the process is better

30N

Physics "what does the size of friction have to do with it"
Put more than half a cup of rice in the glass, insert a chopstick in the middle, press the rice tightly to make the chopsticks stand upright. Then continue to add a little water into the glass. After a while, pick up the chopsticks to lift the glass and tell us the truth

Because the friction coefficient between the expanded rice and the chopsticks is larger, the friction between the rice and the chopsticks is greater than the gravity of the whole cup, so you can lift the rice glass when you pick up the chopsticks
It can be concluded that the friction force is directly related to the pressure and friction coefficient