Answer:
The total mechanical energy does not change if the value of the mass is changed. That is, remain the same
Explanation:
The total mechanical energy of a spring-mass system is equal to the elastic potential energy where the object is at the amplitude of the motion. That is:
(1)
k: spring constant
A: amplitude of the motion = 2.0cm
As you can notice in the equation (1), the total mechanical energy of the system does not depend of the mass of the object. It only depends of the amplitude A and the spring constant.
Hence, if you use a mass of 0.40kg the total mechanical energy is the same as the obtained with a mas 0.20kg
Remain the same
The car would go from zero to 58.0 mph in 2.6 sec.
Since the force on the car is constant, therefore the acceleration of the car would also be constant.
Now for constant acceleration we can use the equation of motion
Using first equation of motion to calculate the acceleration of the car
v=u+at
29=0+a×1.30 ...... Eq. (1)
Again using the first equation of motion
58=0+a*t ....... Eq. (2)
Dividing eq. (2) with equation 1
t=2×1.3
t=2.6 sec
Answer:
14.4 m/s
Explanation:
mass of Anna (Ma) = 68 kg
speed of Anna (Va) = 17 m/s
mass of SandraDay (Ms) = 76 kg
speed of SandraDay (Vs) = 12 m/s
We can find their speed (V) immediately after collision from the conservation of momentum where
(Ma x Va) + (Ms + Vs) = (Ma + Ms) x V
where V = speed immediately after collision
(68 x 17) + (76 + 12) = (68 + 76) x V
2068 = 144 V
V = 2068 / 144 = 14.4 m/s
Answer:
980 kJ
Explanation:
Work = change in energy
W = mgh
W = (1000 kg/m³ × 5.0 m³) (9.8 m/s²) (20 m)
W = 980,000 J
W = 980 kJ
The pump does 980 kJ of work.