Answer:
Speed will be equal to 1.40 m/sec
Explanation:
Mass of the rubber ball m = 5.24 kg = 0.00524 kg
Spring is compressed by 5.01 cm
So x = 5.01 cm = 0.0501 m
Spring constant k = 8.08 N/m
Frictional force f = 0.031 N
Distance moved by ball d = 15.8 cm = 0.158 m
Energy gained by spring
Energy lost due to friction
So remained energy to move the ball = 0.0101 - 0.0048 = 0.0052 J
This energy will be kinetic energy
v = 1.40 m/sec
In a vacuum, all objects fall at the same rate. Meaning that the 100 kg ball will fall at the same speed as the 10 kg ball. Assuming that both objects share the same starting acceleration, they will keep that acceleration until the fall is stopped.
In other words, your answer is the first one, Both objects will accelerate at 9.8 m/s
Answer:
D
Explanation:
Speed = distance / time
her time for the first journey = 20 miles / 60 miles/hr = 1/3 hr
her time for second part of the journey = her remaining distance / her speed = (80 - 20) miles / 30 miles/hr = 60 miles / 30 miles/hr = 2 hrs
total time spend by her = 2 hr+ 1/3 hr = 2 1/3 hrs
her traveling the distance at 40 miles per hour = 80 miles / 40 miles /hr = 2 hrs
the time less she would drive if she drive the entire distance at 40 miles/hr = 2 1/3 hrs - 2 hrs = 1/3 hr
We need to find the average speed of the ball during the motion of 1 m
In order to find that we took several reading and found following times to cover the distance of 1 m
t1 = 2.26 s
t2 = 2.38 s
t3 = 3.02 s
t4 = 2.26 s
t5 = 2.31 s
Now in order to find the average time we can write
So average time to cover the distance of 1 m by ball will be 2.45 s
here 3.02 s is not the average time but we can say it is the median of the readings of all possible values which we can not use in our calculation as average time
Speed = distance/time
Time = 90/60 = 1.5 hours
Speed = 54/1.5
Speed = 36km/h