Answer:
Required energy Q = 231 J
Explanation:
Given:
Specific heat of copper C = 0.385 J/g°C
Mass m = 20 g
ΔT = (50 - 20)°C = 30 °C
Find:
Required energy
Computation:
Q = mCΔT
Q = 20(0.385)(30)
Required energy Q = 231 J
It makes calculations with very large and small numbers easier.
Scientific notation is a system used in order to It makes calculations with very large and small numbers easier. It is useful as it allows very large number that would take a lot of space to write otherwise, and it allows them to be calculated easier.
for example is a incredible large number, but written in this form is immediately understandable and useful for calculation.
Answer:
The height at which the object is moved is 10 meters.
Explanation:
Given that,
Force acting on the object, W = F = 490 N
The gravitational potential energy, P = 4900 J
We need to find the height at which the object is moved. We know that the gravitational potential energy is possessed due to its position. It is given by :

So, the height at which the object is moved is 10 meters. Hence, this is the required solution.
Answer:
E) The average velocity of the car is 90.0 miles per hour in the direction of motion.
Explanation:
Given;
distance covered by the car, d = 90 miles
time taken, t = 60 minutes = 1 hour
The average velocity of the car is given by change in displacement per change in time;
V = Δd / Δt

Therefore, the average velocity of the car is 90.0 miles per hour in the direction of motion.
The inflated balloon shrinks when it is placed in an ice bath with no change in atmospheric pressure.
<u>Explanation:</u>
When the inflated balloon is subjected to an ice bath, it shrinks. This is due to the fact that smaller volume gets occupied by the air/gas inside the balloon as the temperature decreases. Hence, causes the balloon walls to collapse.
An ice bath also lowers the overall air temperature of the balloon inside. As the temperature decreases, the air molecules move more slowly and with lower energy. Because of the particle's lower energy, their collisions with the walls are not enough to keep the inflated balloon.