1. You apply a force of 11.8 N on a 5.1 kg object, pushing it horizontally across a surface where the coefficient of kinetic friction is 0.44.
(a) Determine the frictional force acting.
(b) Determine the object's acceleration.
2. A container of mass 0.5 kg slides along the ice with a speed of 6 m/s when it reaches a rough section where the coefficient of kinetic friction is 1. How long will it take the puck to stop sliding?
3. The gravitational field strength on the surface of Mars is 4.1 N/kg.
a) What would a person weigh on Mars if this person weighs 810 N on Earth?
(b) What is the mass of Mars if its radius is 3.4 x 10^8 m?
Help to any of these question would be appreciated.
Thanks,
Shawn
1a. Fk = u*Fn = u * Mg = 0.44 * 5.1*9.8 = 22 N. The force of kinetic friction is greater than the applied force. please check for errors.
3a. (4.1/9.8) * 810 = 339 N.
Sure, I can help you with these physics questions. Let's start with the first one:
1. To determine the frictional force acting on the object, we can use the formula: frictional force = coefficient of kinetic friction * normal force. The normal force is the force exerted by the surface on the object, which is equal to the weight of the object if it's on a horizontal surface.
The normal force can be calculated using the formula: normal force = mass * gravitational acceleration. In this case, the mass is 5.1 kg and the gravitational acceleration is approximately 9.8 m/s^2. So, normal force = 5.1 kg * 9.8 m/s^2.
Now, we can substitute the values into the formula for the frictional force: frictional force = 0.44 * normal force.
To find the object's acceleration, we can use Newton's second law: force = mass * acceleration. In this case, the force is the applied force of 11.8 N, and the mass is 5.1 kg.
You can now substitute the values into the formula to find the acceleration.
2. To determine how long it will take the container of mass 0.5 kg to stop sliding, we need to consider the deceleration caused by the kinetic friction.
The deceleration caused by the kinetic friction can be calculated using the formula: deceleration = coefficient of kinetic friction * gravitational acceleration.
Using this formula, substitute the values of the coefficient of kinetic friction and the gravitational acceleration to find the deceleration.
The deceleration is equal to the acceleration of the container, but with the opposite sign. So, the acceleration is negative.
To find the time it takes for the container to stop sliding, we can use the equation: final velocity = initial velocity + acceleration * time.
The final velocity is 0 m/s since the container stops sliding, the initial velocity is 6 m/s, and the acceleration is the negative value we calculated earlier.
Solve this equation for time to find how long it will take for the container to stop sliding.
3. To find the weight of a person on Mars, we can use the formula: weight = mass * gravitational field strength.
In this case, the weight on Earth is given as 810 N and the gravitational field strength on Mars is 4.1 N/kg. Just divide 810 N by 4.1 N/kg to find the mass.
To find the mass of Mars given its radius, we can use the formula: gravitational field strength = gravitational constant * mass of Mars / radius^2.
You can rearrange this formula to solve for the mass of Mars. The gravitational constant is a constant value that is approximately 6.67430 × 10^-11 N(m/kg)^2.
Substitute the values of the gravitational field strength and the radius of Mars to find the mass.