Watt is a unit for power that is also equal to J/s. We therefore need to convert the minutes to seconds first before answering. Every minute is comprised of 60 seconds. Therefore, 3 minutes are composed of 180 seconds. Multiplying the number of seconds to the given power will give us,
Work = Power x time
= (1500 J/s) x (180 s)
= 270,000 J
Therefore, the answer is letter D.
The answer is:
1. Cure disease
2. Improve livelihoods
3. Understand nature and themselves.
1. Disease has plagued humans since the first man. Therefore, man has always used science to seek a cure for any emerging disease such as cancer today
2. Humans use science to improve livelihoods such as means of faster traveling and increasing yields in the fields
3. Science has been used to understand humans and the environment in which they live. This is evident with the numerous scientific probes that explore the earth and space collecting and analyzing data.
Answer:
It must be 4 times high.
Explanation:
- Assuming that the car can be treated as a point mass, and that the ramp is frictionless, the total mechanical energy must be conserved.
- This means, that at any time, the following must be true:
- ΔK (change in kinetic energy) = ΔU (change in gravitational potential energy)
⇒
- Let's call v₁, to the final speed of the car, and h₁ to the height of the ramp.
So, at the bottom of the ramp, all the gravitational potential energy
must be equal to the kinetic energy of the car (Defining the bottom of
the ramp as our zero reference for the gravitational potential energy):
(1)
- Now, let's do v₂ = 2* v₁
- Replacing in (1) we get:
(2)
- Dividing (2) by (1), and rearranging terms, we get:
- h₂ = 4* h₁
Answer:
137.2J
Explanation:
Ep= mgh
Given,
and we know, g = 9.81 N/kg
Ep= 2 × 9.81 × 7
Ep= 137.2J