Answer:
Cart A
Explanation:
Momentum can be computed by finding the product of mass and velocity. To solve this, you can use the formula below to find the greatest momentum:
p = mv
where:
p = momentum (kgm/s) m = mass (kg) v = velocity (m/s)
Because carts are moving along with the weights, we need to consider the whole system. This means that you need to add in the masses and the mass of the cart.
<u>Cart A:</u>
m = 200kg + 0 kg = 200 kg
v = 4.8 m/s
p = 200kg x 4.8 m/s = 960 kg-m/s
<u>Cart B:</u>
m = 200kg + 20 kg = 220 kg
v = 4.0 m/s
p = 220kg x 4.0 m/s = 880 kg-m/s
<u>Cart C:</u>
m = 200kg + 40 kg = 240 kg
v = 3.8 m/s
p = 240kg x 3.8 m/s = 912 kg-m/s
<u>Cart D:</u>
m = 200kg + 60 kg = 260 kg
v = 3.5 m/s
p = 260kg x 3.5 m/s = 910 kg-m/s
As you can see, Cart A has the greatest momentum.
Answer:
t = 25.5 min
Explanation:
To know how many minutes does Richard save, you first calculate the time that Richard takes with both velocities v1 = 65mph and v2 = 80mph.

Next, you calculate the difference between both times t1 and t2:

This is the time that Richard saves when he drives with a speed of 80mph. Finally, you convert the result to minutes:

hence, Richard saves 25.5 min (25 min and 30 s) when he drives with a speed of 80mph
The child on a swing can be modeled as a simple pendulum. The period of a simple pendulum is given by
Explanation:
An object's weight depends on the pull of the gravitating object but the object'<u>s mass is independent of the gravity. </u>
Efficiency is defined as the measure of the amount of work or energy is conserved in a certain process. At all times, in every process, work or energy is always lost or wasted due to certain interference. Not all work given is converted to useful work or energy. Thus , efficiency is calculated by dividing the energy or work output to the energy or work input then the value is multiplied by 100 to express efficiency as percentage.
Efficiency = work output / work input
Efficiency = (1020 J / 1200 J) = 85%