Explain how acceleration can be slowing down.
Calculate the impact force of a 50 kg object travelling at 100km/hr.
(Momentum = mass x velocity)
Calculate the momentum of a tennis ball of 50 g moving at a velocity of 25m/s.
Acceleration is a measure of how fast the velocity of an object changes over time. It is generally understood as a change in velocity per unit time. Positive acceleration refers to an increase in velocity, while negative acceleration or deceleration refers to a decrease in velocity. When we say that acceleration can be slowing down, we mean that the object's velocity is decreasing over time.
To calculate the impact force of a moving object, you need to use the concept of momentum. Momentum is the product of an object's mass and velocity. The formula for momentum is:
Momentum = mass x velocity
To calculate the impact force of a 50 kg object traveling at 100 km/hr (which needs to be converted to meters per second), you can use the following steps:
Step 1: Convert the speed from km/hr to m/s. To convert km/hr to m/s, divide the speed by 3.6 since there are 3.6 meters in every kilometer.
100 km/hr ÷ 3.6 = 27.78 m/s (rounded to two decimal places)
Step 2: Calculate momentum using the formula:
Momentum = mass x velocity
Momentum = 50 kg x 27.78 m/s = 1389 Ns (rounded to the nearest whole number)
Since momentum is defined as the product of mass and velocity, it does not directly represent force. To calculate the impact force, you would need additional information related to the collision, such as the time duration of the impact or the change in momentum during the impact. Once you have this information, you can apply Newton's second law of motion (F = ΔP/Δt) to calculate the impact force, where ΔP is the change in momentum and Δt is the duration of the impact.
Moving on to the second question:
To calculate the momentum of a tennis ball with a mass of 50 g moving at a velocity of 25 m/s:
Step 1: Convert the mass from grams to kilograms. Since there are 1000 grams in a kilogram, divide the mass by 1000.
50 g ÷ 1000 = 0.05 kg
Step 2: Calculate momentum using the formula:
Momentum = mass x velocity
Momentum = 0.05 kg x 25 m/s = 1.25 kg m/s.