Question

The elevator can safely lift 300 kg. If John (850 N), Betty (530 N), Robert (740 N), and Alice (610 N) all get in the elevator at once, can it safely carry them up to the third floor?

a) Yes
b) No

Answer 1

The elevator can safely carry John, Betty, Robert, and Alice to the third floor, as their combined mass of 278.5 kg is less than the elevator's maximum lifting capacity of 300 kg.

Step-by-step explanation:

The question involves determining whether an elevator with a maximum safe lifting capacity of 300 kg can carry four people with given weights measured in newtons to the third floor. To answer this question, we first need to convert the weight measurements from newtons to kilograms, considering that the weight (W) is equal to the mass (m) times the acceleration due to gravity (g), which is approximately 9.8 m/s2.

Using this relationship, we can calculate each person's mass by dividing their weight by the acceleration due to gravity:

• John's mass: 850 N / 9.8 m/s2 ≈ 86.7 kg
• Betty's mass: 530 N / 9.8 m/s2 ≈ 54.1 kg
• Robert's mass: 740 N / 9.8 m/s2 ≈ 75.5 kg
• Alice's mass: 610 N / 9.8 m/s2 ≈ 62.2 kg

Next, we add up the masses of all four people:
86.7 kg + 54.1 kg + 75.5 kg + 62.2 kg = 278.5 kg

Since the total mass of all four people is 278.5 kg, which is less than the elevator's maximum safe lifting capacity of 300 kg, the elevator can safely carry John, Betty, Robert, and Alice up to the third floor. Therefore, the answer is (a) Yes.