Final answer:
To determine the bicyclist's instantaneous speed at a given time, one must have a velocity-time graph or function. Without this, the speed cannot be calculated directly. If a function is given, the speed is found by evaluating the function at the specific time and converting the result to the desired units.
Step-by-step explanation:
How to Determine the Bicyclist's Instantaneous Speed
Instantaneous speed at any given time is the magnitude of instantaneous velocity and can be determined if we have a velocity-time graph or a mathematical function describing the velocity over time. For the question about the bicyclist's instantaneous speed at t3 hrs, one would need specific details regarding the cyclist's motion or the appropriate formula representing that motion in order to calculate the speed at that specific hour.
In the absence of information such as a velocity-time graph or a distance-time function, we cannot provide the exact value of the bicyclist's instantaneous speed. However, if you have an equation that represents the velocity of the bicyclist as a function of time, you can find the instantaneous speed by evaluating the velocity function at t3 and taking its absolute value, as speed is scalar and velocity is a vector.
Example Calculation
Let's say a bicyclist's velocity (v) as a function of time (t) is represented by v(t) = 5t² (purely hypothetical). To find the instantaneous speed at t3 hours, we'd evaluate the function at that time: if t3 = 2 hours, then v(t) = 5(2²) = 20 m/s. The instantaneous speed is, therefore, 20 m/s.
Remember, 1 meter per second (m/s) is approximately equal to 2.237 miles per hour (mph). So, to get the speed in miles per hour, multiply by 2.237. Following the example, the speed would be 20 m/s * 2.237 mph/m/s = 44.74 mph.