Moving uniformly rectilinearly, the body in 10 s passed 200 cm.

Moving uniformly rectilinearly, the body in 10 s passed 200 cm. During what time this body moving at the same speed will cover the path of 0.3 km.

1). If the body moves uniformly and rectilinearly, while during the time t₁ = 10 s the body has passed S₁ = 200 cm = 0.2 m, then its speed is determined by the formula:

v = S₁ / t₁. We get the speed value:

v = 0.2 m: 10 s; v = 0.02 m / s.

To find how long it takes t₂ this body, moving at the same speed, will cover the path S₂ = 0.3 km = 300 m, we use the formula:

t₂ = S₂ / v. We get the value:

t₂ = 300 m: 0.02 m / s; t₂ = 15000 s = 250 min = 4 h 10 min.

Answer: for a time equal to 4 hours 10 minutes.

2). Since the area of ​​a roller working on asphalt paving is S = 0.12 m ^ 2, and its weight is F = 48 kN = 48000 N, the pressure p that it exerts on the road is determined by the formula:

p = F / S. We get the pressure value:

p = 48000 N: 0.12 m ^ 2; p = 400000 Pa = 0.4 MPa.

Answer: the pressure is 0.4 MPa.