Let's break down the units and their relationships: Joule (J): The unit of energy. Energy is the capacity to do work. Second (s): The unit of time. Angular Momentum (L): A measure of an object's rotational inertia. It's calculated as the product of the object's moment of inertia (I) and its angular velocity (ω) : L=Iω Now, let's look at the units involved in angular momentum: Moment of Inertia (I): Measured in kilogram-meter squared ( kg⋅m2 ) Angular Velocity ( ω) : Measured in radians per second ( rad∕s ) Combining these, the units of angular momentum are: L=Iω=(kg⋅m2)(rad∕s)=kg⋅m2∕s Since radians are dimensionless, we can simplify this to kg⋅m2∕s. Notice that this is equivalent to Joulesecond (J⋅s). Therefore, Joule-second (J⋅s) is the unit of angular momentum. Let's address why the other options are incorrect: Option A: Energy - Energy is measured in Joules (J), not Joule-seconds (J⋅s). Option B: Power - Power is the rate at which energy is transferred, measured in Watts (W), which is equivalent to Joules per second (J∕s). Option D: Linear momentum - Linear momentum is a measure of an object's mass in motion. It's calculated as the product of the object's mass ( m ) and its velocity ( v ): p=mv Linear momentum is measured in kilogram-meters per second (kg⋅m∕s).