Ways by which friction can be increased are :
1. Tyres of all vehicles have grooved designs or treads to make their surface rough. Roughness of a surface increases friction and prevents vehicle from slipping or skidding on a wet or muddy road.
2. Spikes in the shoe soles used by players and athletes increase friction and they get firm grip on the ground. The soles of footwear are also provided with grooved designs to increase friction and avoid slipping.
3. The handles of motorbikes are covered with spiked rubber to provide a good grip and have better control in holding the handles.
