Gardeners would need to use 960 Newtons of force to lift a potted tree 45 centimeters onto a deck. Instead, they set up a lever. If they press the lever down 2 meters, how much force do they use to lift the tree?
432
432 N is the answer, not 480 N
The gravitational force of an object depends on its mass and the acceleration due to gravity. The formula for gravitational force is F = m * g, where F is the force, m is the mass, and g is the acceleration due to gravity.
In this problem, we are given the gravitational force of the rover on Earth (F = 1607.2 N) and we need to find the gravitational force of the rover on the Moon.
Using the formula F = m * g, we can find the mass of the rover. Rearranging the formula, we get m = F / g.
Therefore, on Earth: m = F / g = 1607.2 N / 9.8 m/s^2 = 163.5 kg.
Now, we can use the mass and the acceleration due to gravity on the Moon to find the gravitational force on the Moon:
On the Moon: F = m * g = 163.5 kg * 1.62 m/s^2 = 265.7 N.
Therefore, the gravitational force of the rover on the Moon will be 265.7 N.
So the correct answer is 265.7 N.
The sentence that best describes a self-directed learner is: "She uses her own initiative to set learning goals, find resources, and plan how to carry out investigations."
A self-directed learner is someone who takes an active role in their own learning process, independently setting goals and seeking out resources to achieve them. Such a learner takes responsibility for their own learning and is motivated to explore and discover information and skills. Rushing through a project quickly, completing all projects and homework, or always getting good grades do not necessarily demonstrate self-directed learning.
How much more kinetic energy does a 6-kilogram bowling ball have when it is rolling at 16 mph (7.1 meters per second) than when it is rolling at 14 mph (6.2 meters per second)?
KE=12mv2
266.5 J
151.2 J
1.3 J
35.9 J
When two charged particles are moving toward each other, their velocities decrease until they eventually come to a stop. What happens afterward?
They accelerate in opposite directions.
They accelerate toward each other.
They remain in the same place without moving.
They bond and accelerate together.
When two charged particles are moving towards each other, their velocities decrease until they eventually come to a stop. Afterward, they accelerate in opposite directions.
As the charged particles approach each other, they increase the magnitude of the electric forces between them. These forces cause a decrease in their velocities, which eventually leads to a stop. After the particles stop moving, the electric forces between them cause them to move away from each other. This causes the particles to accelerate in opposite directions.
Therefore, the correct answer is, "They accelerate in opposite directions."
ok
The efficiency of a lever is given by the ratio of the output work to the input work:
Efficiency = Output work / Input work
In this problem, the output work is the work done by the lever to lift the bricks and the input work is the work done by the students to operate the lever. We are given that the students expend 10,300 Joules of energy to lift the bricks, so that is the input work. The output work is the work done on the bricks, which is 6,283 Joules. Therefore, the efficiency of the lever is:
Efficiency = Output work / Input work = 6283/10300 = 0.61 or 61%
So the correct answer is 61%.
Which sentence best describes how a self-directed learner might investigate gravity?
She would think of a way to test the effect of gravity, develop a plan, and carry out the investigation.
She would only join a team of students that is carrying out a gravity experiment.
She would only repeat a gravity experiment that she researched online.
She would only follow her teacher’s instructions for testing the effects of gravity.