A student is thrown in a lake by his teacher, the student has a mass of 70 kg and a volume of 80,000 cm^3. Would the student sink or float? What is the net force on the student?
What is the density of an object that has a mass of 2000 kg and a volume of 1.5 m^3? Would it sink or float in water?
please help with these
density kid=mass/volume=70000g/80,000 cc
= 7/8 g/cm^3 she floats
density object=2000kg/1.5m^2
density water=1E3 kg/m^3=1500kg/1.5m^3
it sinks.
To determine whether the student would sink or float, we can compare his density to the density of water. If the student's density is greater than the density of water, he will sink; if it is less, he will float.
Step 1: Calculate the density of the student:
Density = Mass / Volume
Given:
Mass of the student = 70 kg
Volume of the student = 80,000 cm^3
To convert cubic centimeters to cubic meters:
1 m^3 = 1,000,000 cm^3
So, the volume of the student in cubic meters would be:
Volume = 80,000 cm^3 / 1,000,000 cm^3/m^3 = 0.08 m^3
Now, substitute the values into the density formula:
Density = 70 kg / 0.08 m^3
Step 2: Calculate the density of water:
The density of water is approximately 1000 kg/m^3.
Now, compare the student's density with the density of water:
If the student's density is greater than 1000 kg/m^3, he will sink. If it's less than 1000 kg/m^3, he will float.
To calculate the net force on the student, we need to consider the forces acting on him while in the water. The two main forces at play are buoyancy and gravity.
Buoyancy Force: This force is equal to the weight of the water displaced by the student. It can be calculated using the formula:
Buoyancy Force = Density of Water × Volume of Displaced Water × Acceleration due to Gravity
Gravity Force: This is the force pulling the student down, which can be calculated as:
Gravity Force = Mass × Acceleration due to Gravity
The net force on the student can be determined by subtracting the buoyancy force from the gravity force:
Net Force = Gravity Force - Buoyancy Force
Given:
Mass of the student = 70 kg
Volume of the student = 80,000 cm^3
Step 1: Calculate the volume of the displaced water:
The volume of displaced water is equal to the volume of the student because when immersed, the water fills the space previously occupied by the student.
Step 2: Calculate the buoyancy force:
Buoyancy Force = Density of Water × Volume of Displaced Water × Acceleration due to Gravity
Step 3: Calculate the gravity force:
Gravity Force = Mass × Acceleration due to Gravity
Step 4: Calculate the net force:
Net Force = Gravity Force - Buoyancy Force
Now, let's calculate the density and determine whether the object will sink or float:
Given:
Mass of the object = 2000 kg
Volume of the object = 1.5 m^3
To calculate the density:
Density = Mass / Volume
Substitute the given values into the density formula:
Density = 2000 kg / 1.5 m^3
To determine if the object will sink or float in water, we need to compare its density with the density of water.
If the density of the object is greater than the density of water, it will sink. If it is less, it will float.