Answer:
Explanation:
Kinetic energy is energy due to motion. The formula is half the product of mass and velocity squared.
The mass of the roller coaster car is 2000 kilograms and the car is moving 10 meters per second.
Substitute these values into the formula.
Solve the exponent.
- (10 m/s)²= 10 m/s * 10 m/s= 100 m²/s²
Multiply the first two numbers together.
Multiply again.
- 1 kilogram square meter per square second is equal to 1 Joule.
- Our answer of 100,000 kg*m²/s² is equal to 100,000 Joules.
The roller coaster car has <u>100,000 Joules</u> of kinetic energy.
The answer is true. It tells me I have to have 20 characters.
Kinetic energy = (1/2) (mass) (speed)²
BUT . . . in order to use this equation just the way it's written,
the speed has to be in meters per second. So we'll have to
make that conversion.
KE = (1/2) · (1,451 kg) · (48 km/hr)² · (1000 m/km)² · (1 hr/3,600 sec)²
= (725.5) · (48 · 1000 · 1 / 3,600)² (kg) · (km·m·hr / hr·km·sec)²
= (725.5) · ( 40/3 )² · ( kg·m² / sec²)
= 128,978 joules (rounded)
Answer: Density
Explanation: Recall Archimedes Principle. There are two forces acting an object submerged in a liquid: the force of gravity and the (opposite directed) force of buoyancy. The buoyancy is proportional to the mass of the liquid displaced by the submerged part of the object.
Density is the ratio of mass to volume. Therefore if the density of the submerged object is higher than that of the displaced liquid, the net force will point in the direction of the gravity (object will sink). In the opposite case, the net force will point in the direction of the buoyant force (upward) and the object will float.
