Mechanical waves require a medium to travel, but electromagnetic waves do not.
We have 2 conditions of balance. First of all, the total forces have to have a net sum of 0 since the bridge is balancing. Hence, if we denote by F1 the force of the first pole, F2 the power of the second pole (the one closer to the car), W the weight of the bridge and w the weight of the car, we have that W+w=F1+F2=4.196*10^5 N.
We also have that it does not rotate. Hence, taking as origin of our frame of reference the car, we have that 5*F2+4*W=9*F2 by calculating the distances from our point of reference. Thus yields 5F2+8*10^5=9F2. When we solve the system of equations that is created above (best way here is by substitution), we get that F1=2.07*10^5 N while F2=2.126*10^5 N . Each pole takes up around half the weight but due to the car the pole closer to it has more weight to bear; nevertheless the car does not weigh a lot so the difference is small.
Answer:
Force exerted on the ball, F = -4900 N
Explanation:
It is given that,
Mass of the ball, m = 0.14 kg
Initial speed of the ball, u = +30 m/s
Final speed of the ball, v = -40 m/s (opposite direction)
Time taken, t = 0.002 s
Let F is the force exerted on the baseball. We know that the force exerted on an object is equal to the product of mass and acceleration. Using second law of motion, the force is given by :
F = ma
F = -4900 N
So, the force exerted on the baseball is -4900 N and it is exerted in opposite direction. Hence, this is the required solution.
if you multiply the mass of an object by the acceleration due to gravity, you will obtain the object's weight. mass is an intrinsic property of matter
looks like a good answer ...
